TWI773975B - Sulfonium compound, chemically amplified resist composition, and patterning process - Google Patents

Abstract

A novel sulfonium compound of formula (A) and a chemically amplified resist composition comprising the same as a PAG are provided. When processed by photolithography using KrF or ArF excimer laser, EB or EUV, the resist composition has a high sensitivity and reduced acid diffusion and is improved in lithography properties.

Description

Peronium compound, chemically amplified photoresist composition, and pattern forming method

The present invention relates to a peronium compound, a chemically amplified photoresist composition, and a pattern forming method.

In recent years, along with the high integration and high speed of LSI, the miniaturization of pattern rules is required. Among them, far-ultraviolet lithography and extreme ultraviolet (EUV) lithography are regarded as promising next-generation microfabrication technologies. Among them, photolithography using an ArF excimer laser is an indispensable technique for ultra-fine processing of 0.13 μm or less.

ArF lithography has been partially used since the manufacture of devices at the 130nm node, and it has become the main lithography technology from the 90nm node device. As the lithography technology of the next 45nm node, 157nm lithography using F ₂ laser was initially regarded as promising, but due to various problems, it was accused of delaying development. Liquids with higher refractive index than air such as glycol and glycerin can design the aperture number (NA) of the projection lens to be 1.0 or more and achieve high-resolution ArF immersion lithography (Non-Patent Document 1), and is in the practical stage. In order to perform this immersion lithography, a photoresist composition that is not easily dissolved in water is sought.

In ArF lithography, in order to prevent the deterioration of precise and expensive optical system materials, a high-sensitivity photoresist composition that can exhibit sufficient resolution with a small exposure amount is required. In terms of the realization method, generally, those that are highly transparent at a wavelength of 193 nm are selected as the respective components. For example, for the base resin, it has been proposed that polyacrylic acid and its derivatives, norbornene-maleic anhydride alternating polymers, polynorbornene and ring-opening metathesis polymers, ring-opening metathesis polymer hydrides, etc., can improve the transparency of the resin itself. Sexuality has achieved some degree of success.

In recent years, both positive dimming photoresist developed with alkaline aqueous solution and negative dimming photoresist developed with organic solvent have attracted attention. In order to analyze a very fine hole pattern that cannot be achieved by positive tone exposure by negative tone exposure, a negative pattern is formed by organic solvent development using a high-resolution positive photoresist composition. In addition, it has also been considered to obtain twice the resolving power by combining the two-time development of the alkaline aqueous solution development and the organic solvent development. As the ArF photoresist composition for negative tone development using an organic solvent, a conventional positive type ArF photoresist composition can be used, and the pattern forming method using the same is described in Patent Documents 1 to 3.

In order to cope with the rapid miniaturization in recent years, the development of processing technology and photoresist composition has also been advanced. There are also various studies on photoacid generators, and generally, a perylium salt composed of a triphenyl perionium cation and a perfluoroalkanesulfonic acid anion is used. However, the generated acid, namely perfluoroalkane sulfonic acid, especially perfluorooctane sulfonic acid (PFOS), has concerns about refractory decomposability, bioconcentration, and toxicity, and is difficult to apply to photoresist compositions. Photoacid generator of alkanesulfonic acid. However, when it is used in a photoresist composition, the diffusion of the generated acid is large, and it is difficult to achieve high resolution. In response to this problem, various partially fluorine-substituted alkanesulfonic acids and salts thereof have been developed. For example, Patent Document 1 describes the generation of photoacids that generate α,α-difluoroalkanesulfonic acid by exposure as a conventional technique. Specifically, 1,1-difluoro-2-(1-naphthyl)ethanesulfonic acid di(4-tert-butyl) was described Phenyl) iodonium, a photoacid generator that produces α,α,β,β-tetrafluoroalkanesulfonic acid. However, although these fluorine substitution ratios are all reduced, since they do not have decomposable substituents such as ester structures, they are not sufficient from the viewpoint of environmental safety due to easy decomposability. There is a limit to molecular design of varying size, and there are problems such as expensive starting materials containing fluorine atoms.

In addition, with the reduction of circuit line width, the influence of contrast deterioration due to acid diffusion in the photoresist composition is more serious. The reason is that the size of the pattern approaches the acid diffusion length, so the size shift on the wafer relative to the value of the size shift of the mask (the mask error factor (MEF)) becomes larger, resulting in reduced mask fidelity and a rectangular pattern. Sexual deterioration. Therefore, in order to fully benefit from the advantages of the shorter wavelength and higher NA of the light source, it is necessary to increase the dissolution contrast or suppress the acid diffusion more than the conventional materials. As one of the improvement measures, when the baking temperature is lowered, the acid diffusion is reduced, and as a result, the MEF can be improved, but the sensitivity is inevitably lowered.

When a bulky substituent or polar group is introduced into the photoacid generator, it is effective for suppressing acid diffusion. In Patent Document 4, it is described that 2-oxoyloxy-1,1,3,3,3-pentafluoropropane-1-, which is excellent in solubility and stability for photoresist solvents, and can be designed in a wide range of molecules A photoacid generator of sulfonic acid, especially, photogenerated 2-(1-adamantyloxy)-1,1,3,3,3-pentafluoropropane-1-sulfonic acid into which a bulky substituent is introduced The acid diffusion of the acid generator is small. In addition, Patent Documents 5 to 7 describe photoacid generators in which condensed cyclic lactones, sultones, and thiolactones are introduced as polar groups. A certain degree of performance improvement can be confirmed by the acid diffusion inhibitory effect due to the introduction of polar groups, but the acid diffusion cannot be controlled to a high degree, and the overall lithography performance such as MEF, pattern shape, and sensitivity is not satisfactory. .

In Patent Documents 8 to 14, as photoacid generators, betaine-type photoacid generators having a cationic site and an anion site in the same molecule are described. After exposure, the cationic site is decomposed as the acid is generated, but since it is bonded to the anionic site, the diffusion of the acid can be suppressed without significantly impairing the composition of the generated acid. quantum. However, since the photoacid generator itself lacks solubility with respect to a photoresist solvent and a developing solution, there are also problems such as precipitation during storage, or occurrence of defects after development. A certain degree of performance improvement can be confirmed by such a photoacid generator, but the sensitivity and acid diffusion cannot be controlled to a high degree. It is desired to develop a photoacid generator with higher sensitivity, lower acid diffusion, and excellent solvent solubility. agent.

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2008-281974

[Patent Document 2] Japanese Patent Laid-Open No. 2008-281975

[Patent Document 3] Japanese Patent No. 4554665

[Patent Document 4] Japanese Patent Laid-Open No. 2007-145797

[Patent Document 5] Japanese Patent No. 5061484

[Patent Document 6] Japanese Patent Application Laid-Open No. 2016-147879

[Patent Document 7] Japanese Patent Laid-Open No. 2015-63472

[Patent Document 8] Japanese Patent No. 5317181

[Patent Document 9] Japanese Patent No. 5723802

[Patent Document 10] Japanese Patent No. 5865725

[Patent Document 11] Japanese Patent No. 6130109

[Patent Document 12] Japanese Patent No. 6155013

[Patent Document 13] Japanese Patent Laid-Open No. 2013-8020

[Patent Document 14] Japanese Patent Laid-Open No. 2018-43977

[Non-patent literature]

[Non-Patent Document 1] Journal of photopolymer Science and Technology, Vol. 17, No.4, p587 (2004)

In response to recent demands for high resolution of photoresist patterns, photoresist compositions using conventional photoacid generators cannot sufficiently suppress acid diffusion, and as a result, lithography performance such as contrast, MEF, and line width roughness (LWR) deteriorates. .

The present invention is made in view of the aforementioned circumstances, and aims to provide a novel perium compound, which is used in photolithography using high-energy rays such as KrF excimer laser light, ArF excimer laser light, electron beam (EB), EUV, etc. as the light source Medium, high sensitivity, small acid diffusion, exposure margin (EL), MEF, LWR and other chemically amplified photoresist compositions with excellent photolithography performance; A composition, and a pattern forming method using the chemically amplified photoresist composition.

As a result of diligent research to achieve the aforementioned object, the inventors of the present application have found that a chemically amplified photoresist composition using a perium compound with a specific structure as a photoacid generator has high sensitivity and little acid diffusion, and has microscopic properties such as EL, MEF, and LWR. The invention is excellent in shadowing performance and extremely effective for precise microfabrication, and the present invention has been completed.

That is, the present invention provides the following peronium compound, chemically amplified photoresist composition, and pattern forming method.

1. A perionium compound represented by the following formula (A).

[hua 1]

In the formula, Q ¹ and Q ² are each independently a fluorine atom or a fluorinated alkyl group having 1 to 6 carbon atoms.

Q ³ and Q ⁴ are each independently a hydrogen atom, a fluorine atom, or a fluorinated alkyl group having 1 to 6 carbon atoms.

a is an integer from 1 to 4.

b is 1 or 2.

c is an integer from 0 to 3.

L ^a1 to L ^a4 are each independently a single bond, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, or a urethane bond.

^XL1 and ^XL2 are each independently a single bond, or a divalent hydrocarbon group having 2 to 40 carbon atoms which may also contain a hetero atom.

R ^a is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom.

R ^b and R ^c are each independently a monovalent hydrocarbon group having 2 to 40 carbon atoms which may also contain heteroatoms, and R ^b and R ^c may also be bonded to each other and to the oxygen atom to which they are bonded and the carbon therebetween. Atoms together form a ring.

R ¹ is a (a+1)-valent hydrocarbon group having 1 to 50 carbon atoms which may contain a hetero atom.

R ² is a monovalent hydrocarbon group having 1 to 50 carbon atoms which may contain a hetero atom.

R ³ is a divalent hydrocarbon group having 1 to 50 carbon atoms which may contain a hetero atom.

In addition, when b=1, R ¹ and R ² or R ² and R ³ can also bond with each other and form a ring together with the sulfur atom to which they are bonded. When b=2, R ¹ and R ³ or 2 Rs ¹ can also be bonded to each other and form rings together with the sulfur atoms to which they are bonded.

2. The peronium compound according to 1., which is represented by the following formula (A-1).

[hua 2]

In the formula, Q ¹ to Q ⁴ , L ^a1 to ^{L a4} , XL1 , ^XL2 , R ^a , R ^b , R ^c , R ² , R ³ , a, b and c are the same as described above. R ^d is a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. d is an integer satisfying 0≦d≦4 and 1≦a+d≦5. When d≧2, each R ^d may be the same or different from each other, and two R ^d may be bonded to each other and form a ring together with the atoms to which they are bonded.

3. The peronium compound according to 2. is represented by the following formula (A-2).

In the formula, Q ¹ to Q ⁴ , L ^a1 to ^{L a4} , XL1 , ^XL2 , R ^a to R ^d , a, b, c, and d are the same as described above. ^Re and R ^f are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. e is an integer from 0 to 5. f is an integer from 0 to 4. When e≧2, each ^Re may be the same or different from each other, and two ^Re may be bonded to each other and form a ring together with the atoms to which they are bonded. When f≧2, each R ^f may be the same or different from each other, and two R ^f may be bonded to each other and form a ring together with the atoms to which they are bonded.

4. The peronium compound according to 3. is represented by the following formula (A-3).

In the formula, Q ¹ to Q ³ , L ^a1 to ^{L a4} , XL1 , ^XL2 , R ^a to R ^f , a, b, d, e and f are the same as described above.

5. A photoacid generator consisting of the perionium compound according to any one of 1. to 4.

6. A chemically amplified photoresist composition comprising: a photoacid generator as described in 5.; and a base resin containing a repeating unit represented by the following formula (a1) or (a2).

In the formula, R ^A is each independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. Z ^A is a single bond, phenylene extension, naphthylene extension or (main chain)-C(=O)-OZ ^{A1-, Z A1 is} a carbon number 1 which may also contain hydroxyl, ether bond, ester bond or lactone ring ~10 alkanediyl, or phenylene or naphthylene. Z ^B is a single bond or (main chain)-C(=O)-O-. X ^A and X ^B are each independently an acid labile group. R ¹¹ is a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. n is an integer from 0 to 4.

7. The chemically amplified photoresist composition according to 6., wherein the base resin further contains a repeating unit represented by the following formula (b1) or (b2).

In the formula, R ^A is each independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. Y ^A is a hydrogen atom, or contains at least one selected from the group consisting of a hydroxyl group, a cyano group, a carbonyl group, a carboxyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, and a carboxylic acid anhydride The polar group of the above structure. m is 1 or 2.

8. The chemically amplified photoresist composition according to 6. or 7., wherein the base resin further contains at least one selected from the repeating units represented by the following formulae (c1) to (c3).

In the formula, R ^A is each independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

Z ¹ is a single bond, a phenylene group, -OZ ¹¹ -, -C(=O)-OZ ¹¹ - or -C(=O)-NH-Z ¹¹ -. Z ¹¹ is an alkanediyl group having 1 to 20 carbon atoms, an alkenediyl group having 2 to 20 carbon atoms, or a phenylene group, and may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

Z ² is a single bond, or -Z ²¹ -C(=O)-O-. Z ²¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom.

Z ³ is a single bond, methylene, ethylidene, phenylene, fluorinated phenylene, -OZ ³¹ -, -C(=O)-OZ ³¹ - or -C(=O)-NH-Z ^31- . Z ³¹ is an alkanediyl group having 1 to 6 carbon atoms, an alkenediyl group having 2 to 6 carbon atoms, or a phenylene group, and may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

R ²¹ and R ²² are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. R ²¹ and R ²² may also be bonded to each other and form a ring together with the sulfur atom to which they are bonded.

M ^- is a non-nucleophilic relative ion.

A ⁺ is an ammonium cation, a pernium cation or an iodonium cation.

9. The chemically amplified photoresist composition according to any one of 6. to 8., further comprising an organic solvent.

10. The chemically amplified photoresist composition according to any one of 6. to 9., further comprising other photoacid generators than the photoacid generator described in 5.

11. The chemically amplified photoresist composition according to 10., wherein the other photoacid generator is represented by the following formula (1) or (2).

In the formula, R ¹⁰¹ , R ¹⁰² and R ¹⁰³ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom. In addition, any two of R ¹⁰¹ , R ¹⁰² and R ¹⁰³ may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. X ^- is an anion selected from the following formulae (1A) to (1D).

In the formula, R ^fa , R ^fb1 , R ^fb2 , R ^fc1 , R ^fc2 and R ^fc3 are each independently a fluorine atom or a monovalent hydrocarbon group having 1 to 40 carbon atoms which may also contain a hetero atom. Also, R ^fb1 and R ^fb2 , and R ^fc1 and R ^fc2 may be bonded to each other and form a ring together with the carbon atom to which they are bonded and the atoms in between. R ^fd is a monovalent hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom.

In the formula, R ²⁰¹ and R ²⁰² are each independently a monovalent hydrocarbon group having 1 to 30 carbon atoms which may also contain a hetero atom. R ²⁰³ is a divalent hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom. Moreover, any two of R ²⁰¹ , R ²⁰² and R ²⁰³ may be bonded to each other and form a ring together with the sulfur atom to which they are bonded. L ^A is a single bond, an ether bond, or a divalent hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom. X ^a , X ^b , X ^c and X ^d are each independently a hydrogen atom, a fluorine atom or a trifluoromethyl group, but at least one of X ^a , X ^b , X ^c and X ^d is a fluorine atom or a trifluoromethyl group base.

12. The chemically amplified photoresist composition according to any one of 6. to 11., further comprising a compound represented by the following formula (3) or (4).

In the formula, R ^q1 is a hydrogen atom, or a monovalent hydrocarbon group with a carbon number of 1 to 40 that may also contain a heteroatom, but the hydrogen atom bonded to the carbon atom at the α position of the sulfo group is substituted by a fluorine atom or a fluoroalkyl group except. R ^q2 is a hydrogen atom, or a monovalent hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom. Mq ⁺ is an onium cation.

13. The chemically amplified photoresist composition according to any one of 6. to 12., further comprising an amine compound.

14. The chemically amplified photoresist composition according to any one of 6. to 13., further comprising a surfactant that is insoluble or insoluble in water but soluble in an alkali developer, and/or insoluble or insoluble in water and Surfactant for alkaline developer.

15. A pattern forming method, comprising the steps of: forming a photoresist film on a substrate using the chemically amplified photoresist composition of any one of 6. to 14.; using the aforementioned photoresist film with KrF excimer laser light, ArF excimer laser light, EB or EUV for exposure; and using a developing solution to develop the aforementioned exposed photoresist film.

16. The pattern forming method according to 15., wherein an alkaline aqueous solution is used as a developing solution to dissolve the exposed portion to obtain a positive pattern in which the unexposed portion is insoluble.

17. The pattern forming method according to 15., wherein an organic solvent is used as a developing solution, and the unexposed part is dissolved to obtain a negative pattern in which the exposed part is not dissolved.

18. The pattern forming method according to 17., wherein the organic solvent is selected from the group consisting of 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3- Hexanone, diisobutyl ketone, methyl cyclohexanone, acetophenone, methyl acetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butenyl acetate, isoamyl acetate ester, propyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl crotonate, ethyl crotonate, methyl propionate, Ethyl Propionate, Ethyl 3-Ethoxypropionate, Methyl Lactate, Ethyl Lactate, Propyl Lactate, Butyl Lactate, Isobutyl Lactate, Amyl Lactate, Isoamyl Lactate, 2-Hydroxyisobutyl Lactate Methyl Acetate, Ethyl 2-Hydroxyisobutyrate, Methyl Benzoate, Ethyl Benzoate, Phenyl Acetate, Benzyl Acetate, Phenyl Methyl Acetate, Benzyl Formate, Phenylethyl Formate, 3-Benzene At least one of methyl propionate, benzyl propionate, ethyl phenylacetate and 2-phenylethyl acetate.

19. The pattern forming method according to any one of 15. to 18., wherein the exposure is immersion exposure performed by inserting a liquid having a refractive index of 1.0 or more between a photoresist film and a projection lens.

20. The pattern forming method according to 19., wherein a protective film is further formed on the photoresist film, the liquid is inserted between the protective film and the projection lens, and immersion exposure is performed.

The peronium compound of the present invention is useful as a photoacid generator used in a chemically amplified photoresist composition. When patterning is performed using the chemically amplified photoresist composition containing the perium compound of the present invention as a photoacid generator, acid diffusion is suppressed to a high degree, and patterns with excellent lithography performance such as EL, MEF, and LWR can be formed.

[Fig. 1] ¹ H-NMR spectrum of PAG-1 obtained in Example 1-1-6.

[ Fig. 2 ] ¹ H-NMR spectrum of PAG-2 obtained in Example 1-2.

[ Fig. 3 ] ¹ H-NMR spectrum of PAG-4 obtained in Example 1-4.

[ Fig. 4 ] ¹ H-NMR spectrum of PAG-5 obtained in Example 1-5-3.

[Peronium compound]

The perylene compound of the present invention is represented by the following formula (A).

In formula (A), Q ¹ and Q ² are each independently a fluorine atom or a fluorinated alkyl group having 1 to 6 carbon atoms. Q ³ and Q ⁴ are each independently a hydrogen atom, a fluorine atom, or a fluorinated alkyl group having 1 to 6 carbon atoms.

In formula (A), a is an integer of 1 to 4, preferably 1. b is 1 or 2. c is an integer from 0 to 3, preferably 1.

In formula (A), L ^a1 to L ^a4 are each independently a single bond, ether bond, ester bond, sulfonate bond, carbonate bond or urethane bond. L ^a1 is preferably a single bond, ether bond or ester bond, more preferably a single bond. L ^a2 is preferably a single bond, an ether bond or an ester bond, more preferably an ether bond. L ^a3 is preferably a single bond, ether bond or ester bond, more preferably a single bond. L ^a4 is preferably a single bond, ether bond or ester bond, more preferably a single bond.

In formula (A), X ^L1 and X ^L2 are each independently a single bond, or a divalent hydrocarbon group having 2 to 40 carbon atoms which may also contain a hetero atom. The divalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include an alkanediyl group, a divalent saturated cyclic hydrocarbon group, and the like. Examples of the aforementioned hetero atoms include an oxygen atom, a nitrogen atom, a sulfur atom, and the like. X ^L1 and X ^L2 are preferably single bonds.

The divalent hydrocarbon group having 2 to 40 carbon atoms which may also contain a hetero atom represented by ^XL1 and ^XL2 is preferably shown below. In addition, in the following formula, * represents the bond with L ^a1 and L ^a2 , and the bond with L ^a3 and L ^a4 .

[Chemical 14]

Among them, ^XL -1 to ^XL -22 and ^XL -47 to ^XL -49 are preferable, and ^XL -1 to ^XL -17 are more preferable.

In the formula (A), R ^a is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, th Tributyl, tert-pentyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, cyclopentyl, cyclohexyl, 2-ethylhexyl, cyclopentylmethyl, cyclopentyl Ethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, tricyclo[5.2.1.0 ^2,6 ]decyl, adamantyl, adamantylmethyl and other alkyl groups; phenyl, naphthyl, anthracenyl and other aryl groups, etc. In addition, a part of the hydrogen atom of the aforementioned monovalent hydrocarbon group can also be substituted with a group containing heteroatoms such as oxygen atom, sulfur atom, nitrogen atom, halogen atom, etc., and an oxygen atom, sulfur atom can also be inserted between the carbon atoms of these groups. , nitrogen atom and other heteroatom groups, the result may also contain hydroxyl, cyano, carbonyl, ether bond, ester bond, sulfonate bond, carbonate bond, urethane bond, amide bond, imide bond, lactone ring, sultone ring, thiolactone ring, lactamide ring, sultam ring, carboxylic acid anhydride (-C(=O)-OC(=O)-), haloalkane Base et al. Among them, R ^a is preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms, more preferably a hydrogen atom or a methyl group, and even more preferably a methyl group.

In formula (A), R ^b and R ^c are each independently a monovalent hydrocarbon group having 2 to 40 carbon atoms which may also contain heteroatoms, and R ^b and R ^c may also be bonded to each other and to the oxygen atom to which they are bonded. together with the carbon atoms in between to form a ring. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include the same monovalent hydrocarbon groups as those exemplified in the description of R ^a . When a part of the hydrogen atoms of the aforementioned monovalent hydrocarbon group is substituted with a halogen atom, it is preferably substituted with a fluorine atom.

When R ^b and R ^c are not bonded to each other and form a ring structure, they form an acyclic acetal structure together with their adjacent oxygen atoms. When R ^b and R ^c are bonded to each other to form a ring, they form a cyclic acetal structure together with their adjacent oxygen atoms. Among these, in consideration of the stability of the acetal structure, it is preferable to form a cyclic acetal structure, and among the cyclic acetal structures, a five-membered ring, a six-membered ring or a seven-membered ring acetal structure is more preferable.

Specific examples of acyclic or cyclic acetal structures include those shown below, but are not limited to these. In addition, in the following formula, R ^a is the same as described above, and the dotted line is an atomic bond with L ^a3 .

In formula (A), R ¹ is a (a+1)-valent hydrocarbon group having 1 to 50 carbon atoms which may also contain a hetero atom, preferably one having 1 to 20 carbon atoms.

The hydrocarbon group represented by R ¹ may be linear, branched, or cyclic, and may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Although the specific structure is mentioned below, it is not limited to these. In addition, in the following formula, the dotted line is the atomic bond of S ⁺ and ^La4 .

[Chemical 19]

R ¹ is preferably an aromatic hydrocarbon group, more preferably a group derived from benzene or naphthalene, and even more preferably a group derived from benzene.

In formula (A), R ² is a monovalent hydrocarbon group having 1 to 50 carbon atoms which may also contain a hetero atom, preferably one having 1 to 20 carbon atoms. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include monovalent aliphatic hydrocarbon groups such as alkyl groups and alkenyl groups, and monovalent aromatic groups such as aryl groups and aralkyl groups. Hydrocarbyl.

Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, cyclopentyl, and cyclohexyl , cycloheptyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, adamantyl, etc. As said alkenyl group, a vinyl group, an allyl group, a propenyl group, a butenyl group, a hexenyl group, a cyclohexenyl group, etc. are mentioned.

The aforementioned aryl groups include: phenyl; 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-ethylphenyl, 4-tert-butylphenyl, 4-n-butyl Alkyl phenyl, 2,4-dimethylphenyl and other alkyl phenyl; naphthyl; methyl naphthyl, ethyl naphthyl and other alkyl naphthyl; dimethyl naphthyl, diethyl naphthyl and other two Alkyl naphthyl etc. As said aralkyl group, a benzyl group, a 1-phenylethyl group, a 2-phenylethyl group, etc. are mentioned.

In addition, a part of the hydrogen atoms of these groups can also be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and a part of carbon atoms of these groups can also be substituted with oxygen atoms, sulfur atoms, etc. , nitrogen atom and other heteroatom groups, and as a result may also contain hydroxyl, cyano, carbonyl, ether bond, ester bond, sulfonate bond, carbonate group, lactone ring, sultone ring, carboxylic acid anhydride, haloalkane Base et al.

Examples of the monovalent aliphatic hydrocarbon group containing a hetero atom include: 2-side oxycyclopentyl, 2-side oxycyclohexyl, 2-side oxypropyl, 2-side oxyethyl, 2-cyclopentyl -2-side oxyethyl, 2-cyclohexyl-2-side oxyethyl, 2-(4-methylcyclohexyl)-2-side oxyethyl and other alkyl groups containing side oxy. Examples of the monovalent aromatic hydrocarbon group containing a hetero atom include heteroaryl groups such as thienyl groups; hydroxyphenyl groups such as 4-hydroxyphenyl groups; fluorinated phenyl groups such as fluorophenyl groups and difluorophenyl groups; 4-methoxyphenyl groups , 3-methoxyphenyl, 2-methoxyphenyl, 4-ethoxyphenyl, 4-tert-butoxyphenyl, 3-tert-butoxyphenyl and other alkoxyphenyl ; Methoxynaphthyl, ethoxynaphthyl, n-propoxynaphthyl, n-butoxynaphthyl and other alkoxynaphthyl groups; Dimethoxynaphthyl, diethoxynaphthyl and other dialkoxynaphthyl groups Naphthyl; 2-phenyl-2-oxyethyl, 2-(1-naphthyl)-2-oxyethyl, 2-(2-naphthyl)-2-oxyethyl such as aryl side oxyalkyl groups, etc.

Among these, R ² is preferably a monovalent aromatic hydrocarbon group which may also contain a hetero atom, more preferably an aryl group which may also contain a hetero atom, and even more preferably a phenyl group, an alkylphenyl group or a fluorinated phenyl group.

In the formula (A), R ³ is a divalent hydrocarbon group having 1 to 50 carbon atoms which may also contain a hetero atom, preferably one having 1 to 20 carbon atoms. The aforementioned divalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include methylene, ethylidene, propane-1,3-diyl, butane-1,4 -diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9 -diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane -1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, heptadecan-1,17-diyl and other linear alkanediyl groups; cyclopentane Divalent saturated cyclic hydrocarbon groups such as alkanediyl, cyclohexanediyl, norbornanediyl and adamantanediyl; divalent aromatic hydrocarbon groups such as phenylene, naphthylene and the like. In addition, a part of the hydrogen atoms of these groups can also be substituted with alkyl groups such as methyl, ethyl, propyl, n-butyl, tert-butyl, etc., or hetero groups such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. The group of atoms may, as a result, contain a hydroxyl group, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride, a haloalkyl group, and the like. Among these, R ³ is preferably a divalent aromatic hydrocarbon group, more preferably a phenylene group, or a phenylene group substituted with an alkyl group or a heteroatom-containing group.

In formula (A), any two of R ¹ , R ² and R ³ may be bonded to each other and form a ring together with the sulfur atom to which they are bonded. In this case, as the periconium cation moiety, those represented by the following formulae and the like can be exemplified.

[hua 20]

The perionium compound represented by the formula (A) is preferably represented by the following formula (A-1).

In formula (A-1), Q ¹ to Q ⁴ , L ^a1 to ^{L a4} , XL1 , ^XL2 , R ^a , R ^b , R ^c , R ² , R ³ , a, b and c are the same as described above. R ^d is a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. d is an integer satisfying 0≦d≦4 and 1≦a+d≦5. When d≧2, each R ^d may be the same or different from each other, and two R ^d may be bonded to each other and form a ring together with the atoms to which they are bonded.

Among the peronium compounds represented by the formula (A-1), those represented by the following formula (A-2) are more preferable.

In formula (A-2), Q ¹ to Q ⁴ , L ^a1 to ^{L a4} , XL1 , ^XL2 , R ^a to R ^d , a, b, c and d are the same as described above. ^Re and R ^f are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. e is an integer from 0 to 5. f is an integer from 0 to 4. When e≧2, each ^Re may be the same or different from each other, and two ^Re may be bonded to each other and form a ring together with the atoms to which they are bonded. When f≧2, each R ^f may be the same or different from each other, and two R ^f may be bonded to each other and form a ring together with the atoms to which they are bonded.

Among the peronium compounds represented by the formula (A-2), those represented by the following formula (A-3) are more preferable.

In the formula, Q ¹ to Q ³ , L ^a1 to ^{L a4} , XL1 , ^XL2 , R ^a to R ^f , a, b, d, e and f are the same as described above.

The perionium compound represented by the formula (A) includes, but is not limited to, those shown below. In addition, in the following formula, Q ³ is the same as described above, and Me is a methyl group.

[Chemical 24]

[Chemical 27]

[Chemical 28]

[Chemical 29]

[Chemical 31]

[Chemical 32]

[Chemical 33]

[Chemical 34]

[Chemical 35]

[Chemical 36]

[Chemical 37]

[Chemical 39]

[Chemical 40]

[Chemical 41]

[Chemical 42]

[Chemical 43]

[Chemical 44]

[Chemical 45]

[Chemical 46]

[Chemical 47]

[Chemical 48]

[Chemical 50]

The peronium compound of the present invention is useful as a photoacid generator. Structural features of the perionium compound of the present invention include a betaine structure having a cationic site and an anion site in the same molecule, and an acetal structure within the molecule. When an acid is generated, a salt compound is formed intermolecularly, and when a photoacid generator is used, a salt compound is formed with the photoacid generator, and it becomes a compound that appears to be huge. In addition, it is presumed that when the acid is generated, the deprotection reaction of the acetal structure by the acid proceeds along with the decomposition of the cation site to form a ketone (or aldehyde) structure of a polar group, whereby the dissolution contrast is improved.

Furthermore, from the above-mentioned reasons, it is presumed that the acid diffusion is also reduced, and the EL, MEF, and LWR are improved, and the depth of focus (DOF) and the dimensional uniformity (CDU) are also improved. In the past, DOF and CDU were in a trade-off relationship between analytical performance and acid diffusion control, but the chemically amplified photoresist composition of the present invention can improve both, which is very useful. In addition, by forming a polar ketone (or aldehyde) structure from the acetal structure, in the positive-type alkali development treatment, the affinity with the alkali developer is improved, and the development defects of the exposed portion are suppressed. On the contrary, in a negative organic solvent development process, the solubility with respect to an organic solvent falls, and the residual film rate of an exposure part improves.

The peronium compound of the present invention can be produced, for example, according to the following scheme. Hereinafter, the synthesis of the perionium compound represented by the following formula (A-a) having a cyclic acetal structure will be described as an example, but the synthesis method is not limited to this.

[Chemical 51]

In the formula, R ^d , ^Re , R ^f , Q ¹ to Q ⁴ , c, d, e and f are the same as described above. X is a halogen atom. X ^- is a halide ion. M ⁺ is the relative cation.

The first step is a step of obtaining the diaryl sulfide of the intermediate A by coupling reaction of the raw material A and the raw material B which can be obtained as a commercial product or by a known synthesis method.

The reaction can be carried out by a known organic synthesis method. Specifically, the raw material A and the raw material B are dissolved in a solvent such as N-methylpyrrolidone, dimethylformamide, and dimethylacetamide, and a copper catalyst and a base are added and reacted. The copper catalyst to be used includes copper iodide (I), copper bromide (I), copper chloride (I), and the like. Again, so Examples of the base to be used include organic bases such as triethylamine, pyridine, and diisopropylethylamine, and inorganic bases such as sodium hydroxide, potassium carbonate, and lithium hydroxide. The reaction temperature is carried out from 80°C to about the boiling point of the solvent used. In terms of reaction time, from the viewpoint of yield, gas chromatography (GC) and silica gel thin layer chromatography (TLC) should be used to track the reaction to complete the reaction, which is ideally about 6 to 24 hours. After completion of the reaction, Intermediate A can be obtained from the reaction mixture by ordinary aqueous work-up. The obtained intermediate A can be purified according to conventional methods such as distillation, silica gel column chromatography, and recrystallization, if necessary.

The second step is a step of oxidizing the diaryl sulfide of the intermediate A to obtain a diaryl arylene.

The reaction can be carried out by a known organic synthesis method. Specifically, the intermediate body A is dissolved in formic acid, acetic acid, or the like, and hydrogen peroxide water is added for the reaction. Excessive use of hydrogen peroxide water for thioethers will result in over-oxidation to sultones. The thioether can also be dissolved in dichloromethane and reacted with m-chloroperbenzoic acid. The reaction temperature is carried out from room temperature to about 50°C. As far as the reaction time is concerned, considering the yield, it is preferable to follow the reaction by GC and TLC to complete the reaction, which is usually about 6 to 24 hours. After completion of the reaction, Intermediate B can be obtained from the reaction mixture by ordinary aqueous work-up. The obtained intermediate B can be purified according to conventional methods such as silica gel column chromatography and recrystallization, if necessary.

The third step is a step of obtaining the cyclic acetal intermediate C by using the corresponding diol for the carbonyl group of the intermediate B.

The reaction can be carried out by a known organic synthesis method. Specifically, the intermediate body B is dissolved in toluene, xylene, etc., and the corresponding diol is added and reacted. During the reaction, the reaction rate can be improved by adding an acid catalyst such as hydrochloric acid, sulfuric acid, nitric acid, p-toluenesulfonic acid, methanesulfonic acid, and trifluoromethanesulfonic acid. In addition, by removing the water produced in the reaction system to the outside of the system, the equilibrium of the reaction system is shifted to the product side, and the reaction can be shortened time. The reaction temperature is carried out at about 80 to 150°C. As far as the reaction time is concerned, considering the yield, it is preferable to follow the reaction by GC and TLC to complete the reaction, which is usually about 6 to 24 hours. After completion of the reaction, Intermediate C can be obtained from the reaction mixture by ordinary aqueous work-up. The obtained intermediate C can be purified according to conventional methods such as silica gel column chromatography and recrystallization, if necessary.

The fourth step is a step of adding a Grignard reagent prepared from halogenated fluorobenzene to the intermediate C to obtain the triaryl perylene salt of the intermediate D.

The reaction can be carried out by a known organic synthesis method. Specifically, Grignard's reagent is prepared from halogenated fluorobenzenes according to the usual method, and intermediate C which has been dissolved in dichloromethane, tetrahydrofuran (THF), etc. is added. After that, trimethylchlorosilane was added dropwise. The reaction temperature is carried out at about 10 to 30°C. In terms of reaction time, from the viewpoint of yield, it is preferable to follow the reaction by TLC to complete the reaction, which is usually about 1 to 2 hours. After completion of the reaction, intermediate D can be obtained from the reaction mixture by ordinary aqueous work-up. The obtained intermediate D can be purified according to conventional methods such as silica gel column chromatography and recrystallization, if necessary. In addition, X- ^of the intermediate D is preferably a chloride ion or a bromide ion.

The fifth step is a step in which intermediate F is obtained by subjecting the obtained intermediate D to salt exchange with intermediate E.

The reaction can be carried out by a known organic synthesis method. Specifically, intermediate D and intermediate E are dissolved or suspended in dichloromethane, methyl isobutyl ketone, or the like, and water is further added and stirred. From the viewpoint of yield, the progress of the reaction is preferably confirmed by TLC. After completion of the reaction, intermediate F can be obtained from the reaction mixture by ordinary aqueous work-up. If necessary, it can be purified by conventional methods such as chromatography and recrystallization.

In the aforementioned scheme, the ion exchange in the fifth step can be easily performed by a known method, for example, refer to Japanese Patent Laid-Open No. 2007-145797.

The sixth step is a step of obtaining the perionium compound (A-a) by the aromatic nucleophilic substitution reaction of the obtained intermediate F.

For the reaction, sodium hydride was suspended in THF, and the THF solution of Intermediate F was added dropwise while cooling the reaction system. From the viewpoint of yield, the progress of the reaction is preferably confirmed by TLC. After completion of the reaction, the perionium compound (A-a) can be obtained from the reaction mixture by ordinary aqueous work-up. If necessary, it can be purified by conventional methods such as chromatography and recrystallization.

In addition, the production method based on the above-mentioned scheme is merely an example, and the production method of the perionium compound of the present invention is not limited to this. In addition, the aforementioned scheme is about the synthesis example of the compound with ether bond. For those skilled in the art, by using organic chemical methods within the scope of common sense, it is also possible to synthesize the compound with ester bond, sulfonate bond, carbonate bond or Peronium compounds with urethane linkages.

[Chemical Amplified Photoresist Composition]

The chemically amplified photoresist composition of the present invention contains: (A) a photoacid generator composed of a perium compound represented by the formula (A); and (B) a base resin as essential components, and contains: (C) an organic solvent as other Element.

If necessary, it may also contain: (D) other photoacid generators; (E) a quencher; in addition, if necessary, may also contain: (F) a surfactant that is insoluble or poorly soluble in water but soluble in an alkaline developer, and/or a surfactant that is insoluble or poorly soluble in water and an alkaline developer Surfactant; in addition, if necessary, it may contain: (G) other components.

The content of the photoacid generator composed of the pericynium compound represented by the formula (A) in the component (A) is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass with respect to 80 parts by mass of the base resin (B) described later. . When the content of the component (A) is within the aforementioned range, the sensitivity and resolution are favorable, and there is no possibility that a foreign matter problem will occur after the development or peeling of the photoresist film, which is preferable. The photoacid generator of (A) component can be used individually by 1 type or in combination of 2 or more types.

[(B) Base resin]

The base resin of the component (B) contains a repeating unit represented by the following formula (a1) or (a2).

In formulae (a1) and (a2), R ^A is each independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. Z ^A is a single bond, phenylene extension, naphthylene extension or (main chain)-C(=O)-OZ ^{A1-, Z A1 is} a carbon number 1 which may also contain hydroxyl, ether bond, ester bond or lactone ring ~10 alkanediyl, or phenylene or naphthylene. Z ^B is a single bond or (main chain)-C(=O)-O-. X ^A and X ^B are each independently an acid labile group. R ¹¹ is a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. n is an integer from 0 to 4.

Although the structure obtained by changing Z ^A in Formula (a1) is mentioned below, it is not limited to these. In addition, in the following formula, R ^A and X ^A are the same as described above.

[Chemical 54]

The polymer containing the repeating unit represented by the formula (a1) is decomposed by the action of an acid to generate a carboxyl group and becomes alkali-soluble.

The acid-labile group is not particularly limited, for example, it is suitable for: a group selected from the following formulae (L1)~(L4); carbon number 4~20, preferably a 3-level alkyl group with carbon number 4~15; each alkyl group They are trialkylsilyl groups of alkyl groups with 1 to 6 carbon atoms; alkyl groups with side oxygen groups of 4 to 20 carbon atoms, etc.

In the formula, the dotted line is an atomic bond (the same applies hereinafter).

In formula (L1), R ^L01 and R ^L02 are: a hydrogen atom; or an alkyl group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms. The aforementioned alkyl group may be linear, branched, or cyclic, and specific examples thereof include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tertiary Butyl, cyclopentyl, cyclohexyl, 2-ethylhexyl, n-octyl, norbornyl, tricyclodecyl, tetracyclododecyl, adamantyl, etc.

R ^L03 is a carbon number of 1 to 18, preferably a monovalent hydrocarbon group of 1 to 10 carbon atoms, which may also contain a group containing a hetero atom such as an oxygen atom. The above-mentioned monovalent hydrocarbon group includes straight-chain, branched or cyclic alkyl groups; a part of these hydrogen atoms is substituted with a hydroxyl group, an alkoxy group, a pendant oxy group, an amino group, an alkylamine group, etc. ; A part of these carbon atoms is substituted with a group containing a heteroatom such as an oxygen atom, etc. Examples of the above-mentioned alkyl group include the same alkyl groups as the above-mentioned alkyl groups represented as R ^L01 and R ^L02 . Moreover, the group shown below etc. are mentioned as a substituted alkyl group.

R ^L01 and R ^L02 , R ^L01 and R ^L03 , or R ^L02 and R ^L03 can also be bonded to each other and form a ring together with the carbon atoms and oxygen atoms to which they are bonded, and R ^L01 and R participating in the formation of the ring when forming the ring ^L02 and R ^L03 are respectively linear or branched alkanediyl groups having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms.

In formula (L2), R ^L04 is: carbon number 4～20, preferably the 3rd-level alkyl group of carbon number 4～15; Each alkyl group is the trialkylsilyl group of the alkyl group of carbon number 1～6 respectively; An alkyl group containing a pendant oxygen group having 4 to 20 carbon atoms; or a group represented by formula (L1). Examples of the tertiary alkyl group include tertiary butyl, tertiary pentyl, 1,1-diethylpropyl, 2-cyclopentylpropan-2-yl, 2-cyclohexylpropan-2-yl, 2- -(Bicyclo[2.2.1]heptan-2-yl)propan-2-yl, 2-(adamantan-1-yl)propan-2-yl, 1-ethylcyclopentyl, 1-butyl ring Pentyl, 1-ethylcyclohexyl, 1-butylcyclohexyl, 1-ethyl-2-cyclopentenyl, 1-ethyl-2-cyclohexenyl, 2-methyl-2-adamantane group, 2-ethyl-2-adamantyl, etc. Examples of the aforementioned trialkylsilyl group include trimethylsilyl, triethylsilyl, dimethyl-tert-butylsilyl, and the like. The aforementioned alkyl group containing a pendant oxygen group may include: 3-oxygen cyclohexyl, 4-methyl-2-oxygen oxane-4-yl, 5-methyl-2-oxygenoxy Heterocyclopentan-5-yl, etc. x is an integer from 0 to 6.

In formula (L3), R ^L05 is an optionally substituted linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, or an optionally substituted aryl group having 6 to 20 carbon atoms. The aforementioned alkyl group which may be substituted may be any of linear, branched and cyclic, and specific examples thereof include: methyl, ethyl, propyl, isopropyl, n-butyl, second Butyl, tert-butyl, tert-pentyl, n-pentyl, n-hexyl, cyclopentyl, cyclohexyl and other straight-chain, branched or cyclic alkyl groups; part of the hydrogen atoms of these groups are substituted with A hydroxyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, a pendant oxygen group, an amino group, an alkylamine group, a cyano group, a mercapto group, an alkylthio group, a sulfo group, and the like. The aforementioned aryl groups that can also be substituted include: phenyl, methylphenyl, naphthyl, anthracenyl, phenanthrenyl, pyrenyl; a portion of the hydrogen atoms of these groups are substituted with hydroxyl, alkoxy, carboxyl, alkane Oxycarbonyl, pendant oxy, amino, alkylamine, cyano, mercapto, alkylthio, sulfo, etc. y is 0 or 1, z is an integer from 0 to 3, 2y+z=2 or 3.

In formula (L4), R ^L06 is an optionally substituted alkyl group having 1 to 8 carbon atoms, or an optionally substituted aryl group having 6 to 20 carbon atoms. The aforementioned alkyl group may be linear, branched, or cyclic. Specific examples of the above-mentioned alkyl group and aryl group include the same alkyl group and aryl group as those described as those represented by R ^L05 , respectively.

R ^L07 to R ^L16 are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 15 carbon atoms which may be substituted. The aforementioned monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, th Tributyl, tert-pentyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentyl Linear, branched or cyclic alkyl groups such as butyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl; a part of these hydrogen atoms is substituted with hydroxyl, alkoxy, carboxyl, alkoxy Carbonyl, pendant oxy, amino, alkylamine, cyano, mercapto, alkylthio, sulfo, etc. Two selected from R ^L07 to R ^L16 may also be bonded to each other and form a ring together with the carbon atoms to which they are bonded (for example, R ^L07 and R ^L08 , R ^L07 and R ^L09 , R ^L07 and R ^L10 , R L07 and R L08 , R L07 and R L09 ^L08 and R ^L10 , R ^L09 and R ^L10 , R ^L11 and R ^L12 , R ^L13 and R ^L14 , etc.), at this time, the group involved in ring formation is a divalent hydrocarbon group with 1 to 15 carbon atoms. Examples of the above-mentioned divalent hydrocarbon group include those obtained by removing one hydrogen atom from those listed as the above-mentioned monovalent hydrocarbon group. In addition, those of R ^L07 -R ^L16 that are bonded to adjacent carbons can also be directly bonded to each other to form a double bond (for example, R ^L07 and R ^L09 , R ^L09 and R ^L15 , R ^L13 and R ^L15 , R ^L14 and R ^L15 , etc.).

Among the acid-labile groups represented by the formula (L1), straight-chain or branched ones include the groups shown below, but are not limited to these.

Among the acid-labile groups represented by formula (L1), cyclic ones include tetrahydrofuran-2-yl, 2-methyltetrahydrofuran-2-yl, tetrahydropyran-2-yl, 2-methyltetrahydropyran- 2-base, etc.

Examples of the acid-labile group represented by the formula (L2) include 3rd butoxycarbonyl, 3rd butoxycarbonylmethyl, 3rd pentyloxycarbonyl, 3rd pentyloxycarbonylmethyl, 1,1 -Diethylpropyloxycarbonyl, 1,1-diethylpropyloxycarbonylmethyl, 1-ethylcyclopentyloxycarbonyl, 1-ethylcyclopentyloxycarbonylmethyl, 1 -Ethyl-2-cyclopentenyloxycarbonyl, 1-ethyl-2-cyclopentenyloxycarbonylmethyl, 1-ethoxyethoxycarbonylmethyl, 2-tetrahydropyranyl Oxycarbonylmethyl, 2-tetrahydrofuryloxycarbonylmethyl, etc.

The acid-labile group represented by the formula (L3) includes: 1-methylcyclopentyl, 1-ethylcyclopentyl, 1-n-propylcyclopentyl, 1-isopropylcyclopentyl, 1-n-propylcyclopentyl Butylcyclopentyl, 1-second-butylcyclopentyl, 1-cyclohexylcyclopentyl, 1-(4-methoxy-n-butyl)cyclopentyl, 1-methylcyclohexyl, 1- Ethylcyclohexyl, 3-methyl-1-cyclopenten-3-yl, 3-ethyl-1-cyclopenten-3-yl, 3-methyl-1-cyclohexen-3-yl, 3-ethyl-1-cyclohexen-3-yl and the like.

The acid-labile group represented by the formula (L4) is preferably a group represented by the following formulae (L4-1) to (L4-4).

In formulas (L4-1) to (L4-4), the dotted lines are the bonding positions and bonding directions. R ^L21 are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms. The aforementioned monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, th Tributyl, tertiary pentyl, n-pentyl, n-hexyl, cyclopentyl, cyclohexyl and other alkyl groups, etc.

The groups represented by formulas (L4-1)~(L4-4) may have stereoisomers (mirror image isomers or non-mirror image isomers), but they are represented by formulas (L4-1)~(L4-4) All these stereoisomers are shown. When the acid-labile group X ^A is a group represented by the formula (L4), various stereoisomers may be contained.

For example, the formula (L4-3) represents one kind or a mixture of two kinds selected from the groups represented by the following formulae (L4-3-1) and (L4-3-2).

In the formula, R ^L21 is the same as described above.

Moreover, the formula (L4-4) represents one type or a mixture of two or more types selected from groups represented by the following formulae (L4-4-1) to (L4-4-4).

In the formula, R ^L21 is the same as described above.

Formulas (L4-1)~(L4-4), (L4-3-1), (L4-3-2), and formulas (L4-4-1)~(L4-4-4) represent them enantiomers and mixtures of enantiomers.

In addition, the bonds of formulas (L4-1) to (L4-4), (L4-3-1), (L4-3-2), and formulas (L4-4-1) to (L4-4-4) The junction directions are each on the exo side with respect to the bicyclo[2.2.1]heptane ring, thereby achieving high reactivity in the acid catalyst desorption reaction (refer to Japanese Patent Laid-Open No. 2000-336121). When producing a monomer having a tertiary exo-alkyl group having a bicyclo[2.2.1]heptane skeleton as a substituent, it may contain the following formulas (L4-1-endo) to (L4-4-endo) Indicates an endo-alkyl-substituted monomer, but in order to achieve good reactivity, the exo ratio is preferably 50 mol % or more, and more preferably, the exo ratio is 80 mol % or more.

In the formula, R ^L21 is the same as described above.

The acid-labile group represented by the formula (L4) includes, but is not limited to, the groups shown below.

In addition, X ^A represents a 3-level alkyl group having 4 to 20 carbon atoms, each alkyl group is a trialkylsilyl group having an alkyl group having 1 to 6 carbon atoms, and an alkane having a pendant oxygen group having 4 to 20 carbon atoms. The bases can be the same as those listed in the description of R ^L04 , respectively.

The repeating unit represented by the formula (a1) includes, but is not limited to, those shown below. In addition, in the following formula, R ^A is the same as that described above.

[Chemical 65]

[Chemical 67]

In addition, these specific examples are the case where Z ^A is a single bond, but when Z ^A is other than a single bond, it may be combined with the same acid-labile group. Specific examples when Z ^A is other than a single bond are as described above.

In formula (a2), n is an integer from 0 to 4, preferably 0 or 1.

The polymer containing the repeating unit represented by the formula (a2), like the repeating unit represented by the formula (a1), is decomposed by the action of an acid to generate a hydroxyl group and become alkali-soluble.

The repeating unit represented by the formula (a2) includes, but is not limited to, those shown below. In addition, in the following formula, R ^A is the same as that described above.

[Chemical 68]

[Chemical 69]

The aforementioned polymer preferably further contains a repeating unit represented by the following formula (b1) or (b2).

In formulas (b1) and (b2), ^RA is the same as described above. Y ^A is a hydrogen atom, or contains at least one selected from the group consisting of a hydroxyl group, a cyano group, a carbonyl group, a carboxyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, and a carboxylic acid anhydride The polar group of the above structure. b is 1 or 2.

The repeating unit represented by the formula (b1) includes, but is not limited to, those shown below. In addition, in the following formula, R ^A is the same as that described above.

[Chemical 74]

[Chemical 75]

[Chemical 77]

[Chemical 80]

The repeating unit represented by the formula (b2) includes, but is not limited to, those shown below. In addition, in the following formula, R ^A is the same as that described above.

[Chemical 81]

As far as the repeating unit represented by formula (b1) or (b2) is concerned, in ArF lithography, it is particularly preferred to have a lactone ring as a polar group, and in KrF, EB and EUV lithography, it is suitable to have a phenol site. .

The said polymer may further contain at least 1 sort(s) chosen from the repeating unit represented by following formula (c1)-(c3).

In the formulae (c1) to (c3), R ^A is the same as described above. Z ¹ is a single bond, a phenylene group, -OZ ¹¹ -, -C(=O)-OZ ¹¹ - or -C(=O)-NH-Z ¹¹ -. Z ¹¹ is an alkanediyl group with 1 to 20 carbon atoms, an alkenediyl group with a carbon number of 2 to 20 or a phenylene group, and may also contain carbonyl (-CO-), ester bond (-COO-), ether bond (-O -) or hydroxyl. Z ² is a single bond, or -Z ²¹ -C(=O)-O-. Z ²¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. Z ³ is a single bond, methylene, ethylidene, phenylene, fluorinated phenylene, -OZ ³¹ -, -C(=O)-OZ ³¹ - or -C(=O)-NH-Z ^31- . Z ³¹ is an alkanediyl group having 1 to 6 carbon atoms, an alkenediyl group having 2 to 6 carbon atoms, or a phenylene group, and may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

In formula (c1), R ²¹ and R ²² are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. Also, R ²¹ and R ²² may be bonded to each other to form a ring together with the sulfur atom to which they are bonded.

Examples of monovalent hydrocarbon groups represented by R ²¹ and R ²² include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, and cyclopropyl Methyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, adamantyl and other alkyl groups; vinyl, allyl, propenyl, butenyl, hexenyl, cyclohexenyl and other alkenes phenyl, naphthyl, thienyl and other aryl groups; benzyl, 1-phenylethyl, 2-phenylethyl and other aralkyl groups, etc., preferably aryl groups. A part of the hydrogen atom of the aforementioned monovalent hydrocarbon group can also be substituted with a group containing heteroatoms such as oxygen atom, sulfur atom, nitrogen atom, halogen atom, etc. Atoms and other heteroatoms may also contain hydroxyl, cyano, carbonyl, ether bond, ester bond, sulfonate bond, carbonate bond, lactone ring, sultone ring, carboxylic acid anhydride, haloalkyl, etc. .

In formula (c1), the non ^- nucleophilic counter ions represented by M- include halide ions such as chloride ions and bromide ions; trifluoromethanesulfonate ions, 1,1,1-trifluoroethanesulfonate ion, fluoroalkyl sulfonate ion such as nonafluorobutanesulfonate ion; toluenesulfonate ion, benzenesulfonate ion, 4-fluorobenzenesulfonate ion, 1,2,3,4,5-pentafluorobenzenesulfonate Aryl sulfonate ions such as ions; alkyl sulfonate ions such as methanesulfonate ions, butane sulfonate ions; bis(trifluoromethylsulfonyl)imide ions, bis(perfluoroethylsulfonyl) ions imide ion, bis(perfluorobutylsulfonyl) imide ion and other imide ions; ) methylated acid ions such as methide ions.

In addition, examples of the non-nucleophilic counter ions include a sulfonic acid anion substituted with a fluorine atom at the α-position represented by the following formula (c1-1), and a fluorine atom at the α-position and β-position represented by the following formula (c1-2). Substituted sulfonic acid anion.

In formula (c1-1), R ³¹ is a hydrogen atom, an alkyl group with 1 to 20 carbon atoms, an alkenyl group with 2 to 20 carbon atoms, or an aryl group with 6 to 20 carbon atoms, and may also contain ether bonds and ester bonds. , carbonyl group, lactone ring or fluorine atom. The aforementioned alkyl group and alkenyl group may be linear, branched, or cyclic.

In formula (c1-2), R ³² is a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an acyl group having 2 to 30 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, Or an aryloxy group having 6 to 20 carbon atoms, and may also contain an ether bond, an ester bond, a carbonyl group or a lactone ring. The aforementioned alkyl group, acyl group, and alkenyl group may be linear, branched, or cyclic.

In the formula (c2), when Z ² is -Z ²¹ -C(=O)-O-, the divalent hydrocarbon group with 1 to 20 carbon atoms represented by Z ²¹ that may also contain a hetero atom can be listed below, but Not limited to these.

In the formula, the dotted line is the atomic bond.

In formulas (c2) and (c3), A ⁺ is a perionium cation or an iodonium cation. The aforementioned periconium cation and iodonium cation are preferably represented by the following formula (c4) and those represented by the following formula (c5), respectively.

[Chemical 85]

In formula (c4), R ⁴¹ , R ⁴² and R ⁴³ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom. In addition, any two of R ⁴¹ , R ⁴² and R ⁴³ may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. In formula (c5), R ⁴⁴ and R ⁴⁵ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom.

The aforementioned monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, Cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, adamantyl and other alkyl groups; vinyl, allyl, propenyl, Alkenyl groups such as butenyl, hexenyl, and cyclohexenyl; aryl groups such as phenyl, naphthyl, and thienyl; aralkyl groups such as benzyl, 1-phenylethyl, and 2-phenylethyl. Among these, an aryl group is suitable. In addition, a part of the hydrogen atom of the aforementioned monovalent hydrocarbon group can also be substituted with a group containing heteroatoms such as oxygen atom, sulfur atom, nitrogen atom, halogen atom, etc., and an oxygen atom, sulfur atom can also be inserted between the carbon atoms of these groups. , nitrogen atom and other heteroatom groups, the result may also contain hydroxyl, cyano, carbonyl, ether bond, ester bond, sulfonate bond, carbonate bond, lactone ring, sultone ring, carboxylic anhydride, haloalkane Base et al.

When any two of R ⁴¹ , R ⁴² and R ⁴³ are bonded to each other and form a ring together with the sulfur atom to which they are bonded, the periconium cation represented by the formula (c4) includes those represented by the following formula.

[Chemical 86]

In the formula, R ⁴⁶ is a monovalent hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom.

Examples of the perionium cation represented by the formula (c4) include those shown below, but are not limited to these.

[Chemical 87]

[Chemical 88]

[Chemical 89]

[Chemical 90]

[Chemical 91]

[Chemical 92]

[Chemical 93]

[Chemical 94]

[Chemical 100]

[Chemical 102]

[Chemical 104]

[Chemical 105]

The iodonium cation represented by the formula (c5) includes, but is not limited to, those shown below.

[Chemical 106]

The aforementioned polymer may further contain a repeating unit having a structure in which a hydroxyl group is protected with an acid-labile group. Such a repeating unit is not particularly limited as long as it has a structure in which one or two or more hydroxyl groups are protected and the protecting group is decomposed by the action of an acid to generate a hydroxyl group, but is preferably represented by the following formula (d1).

In formula (d1), R ^A is the same as described above. R ⁵¹ is a (k+1)-valent hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom. R ⁵² is an acid labile group. k is an integer from 1 to 4.

The repeating unit represented by the formula (d1) includes, but is not limited to, those shown below. In addition, in the following formula, R ^A and R ⁵² are the same as described above.

[Chemical 108]

[Chemical 109]

[Chemical 110]

[Chemical 112]

In the formula (d1), the acid-labile group R ⁵² may be deprotected by the action of an acid to generate a hydroxyl group. The structure of R ⁵² is not particularly limited, but is preferably an acetal structure, a ketal structure, an alkoxycarbonyl group, or the like, and specific examples thereof include those shown below. In addition, in the following formula, the dotted line is an atomic bond.

A particularly desirable acid-labile group for R ⁵² is an alkoxymethyl group represented by the following formula (d2).

In the formula, the dotted line is the atomic bond. R ⁵³ is a monovalent hydrocarbon group having 1 to 15 carbon atoms.

The acid-labile group represented by the formula (d2) includes, but is not limited to, those shown below.

[Chemical 117]

[Chemical 118]

[Chemical 119]

The aforementioned polymer may further contain other repeating units than the aforementioned. For example, it may contain repeating units derived from the following substances: substituted acrylates such as methyl methacrylate, methyl crotonate, dimethyl maleate, dimethyl itonate; maleic acid, fumaric acid, Unsaturated carboxylic acids such as itaconic acid; cyclic olefins such as norbornene, norbornene derivatives, tetracyclo[6.2.1.1 ^3,6 .0 ^2,7 ]dodecene derivatives; Saturated anhydrides; other monomers.

The weight average molecular weight (Mw) of the aforementioned polymer is preferably 1,000-500,000, more preferably 3,000-100,000. When Mw is within this range, sufficient etching resistance can be obtained, and there is no possibility of a decrease in resolution due to the inability to secure the difference in dissolution rate before and after exposure. In addition, in this invention, Mw is a polystyrene conversion measurement value obtained by the gel permeation chromatography (GPC) using THF as a solvent.

In addition, when the molecular weight distribution (Mw/Mn) in the polymer is wide, there is a possibility that foreign matter is observed on the pattern after exposure, or the shape of the pattern deteriorates due to the presence of low molecular weight and high molecular weight polymers. Therefore, the influence of Mw/Mn tends to increase with the miniaturization of pattern rules. Therefore, in order to obtain a photoresist composition suitable for fine pattern size, the Mw/Mn of the aforementioned polymer is preferably narrowly dispersed in the range of 1.0 to 2.0.

烷等。聚合引發劑可列舉：2,2’-偶氮雙異丁腈(AIBN)、2,2’-偶氮雙(2,4-二甲基戊腈)、二甲基2,2-偶氮雙(2-甲基丙酸酯)、過氧化苯甲醯、過氧化月桂醯等。反應溫度宜為50~80℃。反應時間宜為2~100小時，更佳為5~20小時。酸不穩定基可直接使用已導入到單體者，也可於聚合後予以保護化或部分保護化。 An example of the synthesis method of the aforementioned polymer includes a method of polymerizing one or more monomers having an unsaturated bond by adding a radical initiator to an organic solvent and heating. The organic solvent used in the polymerization reaction includes toluene, benzene, THF, diethyl ether, diethyl ether,

alkane etc. The polymerization initiators include 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2-azo Bis(2-methylpropionate), benzyl peroxide, lauryl peroxide, etc. The reaction temperature is preferably 50 to 80°C. The reaction time is preferably 2 to 100 hours, more preferably 5 to 20 hours. The acid-labile group may be directly introduced into the monomer, or may be protected or partially protected after polymerization.

Although the desirable content ratio of each repeating unit in the said polymer can be set to the range (mol%) shown below, for example, it is not limited to this.

(1) One or more of the repeating units represented by formula (a1) or (a2) should preferably be set to 1-60 mol %, more preferably 5-50 mol %, and still more preferably 10-50 mol % %; (II) one or more of the repeating units represented by formula (b1) or (b2) should preferably be set to 40-99 mol %, more preferably 50-95 mol %, and more preferably 50 mol % ~90 mol%; (III) one or more of the repeating units selected from formulas (c1) to (c3) should preferably be set to 0 to 30 mol%, more preferably 0 to 20 mol%, and More preferably, it is 0-10 mol%; and (IV) one or more kinds of repeating units from other monomers are preferably set at 0-80 mol%, more preferably 0-70 mol%, and more Preferably, it is 0~50 mol%.

As for the (B) base resin, one type may be used alone, or two or more types having different composition ratios, Mw and/or Mw/Mn may be used in combination. Moreover, (B) base resin may contain the hydrogenated product of a ring-opening metathesis polymer in addition to the said polymer, and the thing described in Unexamined-Japanese-Patent No. 2003-66612 can be used.

[(C) Organic solvent]

The organic solvent of the component (C) is not particularly limited as long as it can dissolve each of the above-mentioned components and each of the components to be described later. Examples of such organic solvents include ketones such as cyclohexanone and methyl-2-n-pentyl ketone described in paragraphs [0144] to [0145] of JP-A No. 2008-111103; 3-methoxy Ethyl butanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol and other alcohols; propylene glycol monomethyl ether, ethylene glycol Ethers such as monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether; propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, acetone Ethyl acetate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, 3-butyl acetate, 3-butyl propionate, propylene glycol mono-tert-butyl ether acetate and other esters; γ-butyrolactone and other lactones; and their mixed solvents. When an acetal-based acid-labile group is used, in order to accelerate the deprotection reaction of the acetal, a high-boiling alcohol-based solvent, specifically, diethylene glycol, propylene glycol, glycerin, and 1,4-butane may be added. Diol, 1,3-butanediol, etc.

Among these organic solvents, 1-ethoxy-2-propanol, propylene glycol monomethyl ether acetate, cyclohexanone, γ-butane, which are particularly excellent in solubility of the photoacid generator of the component (A) are preferred. Lactones, and their mixed solvents.

The amount of the organic solvent used is preferably 200 to 5,000 parts by mass, more preferably 400 to 3,000 parts by mass, relative to 80 parts by mass of the (B) base resin.

[(D) Other photoacid generators]

The chemically amplified photoresist composition of the present invention may contain a photoacid generator (hereinafter, also referred to as another photoacid generator) other than the component (A) as the component (D). The other photoacid generator is not particularly limited as long as it is a compound that generates acid by irradiation with high-energy rays. Desirable other photoacid generators include those represented by the following formula (1).

In formula (1), R ¹⁰¹ , R ¹⁰² and R ¹⁰³ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. In addition, any two of R ¹⁰¹ , R ¹⁰² and R ¹⁰³ may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include the same monovalent hydrocarbon groups as those exemplified in the description of the formula (c4). In addition, the specific example of the cation of the periconium salt represented by the formula (1) is the same as the specific example of the periconium cation represented by the formula (c4).

In formula (1), X ^- is an anion selected from the following formulae (1A) to (1D).

In formula (1A), R ^fa is a fluorine atom or a monovalent hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include the same monovalent hydrocarbon groups as those exemplified in the description of R ¹¹² in the formula (1A') below.

The anion represented by the formula (1A) is preferably represented by the following formula (1A').

In formula (1A'), R ¹¹¹ is a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. R ¹¹² is a monovalent hydrocarbon group having 1 to 38 carbon atoms which may contain a hetero atom. The aforementioned heteroatom is preferably an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom, etc., more preferably an oxygen atom. From the viewpoint of obtaining high resolution in fine pattern formation, the monovalent hydrocarbon group having 6 to 30 carbon atoms is particularly preferred. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, and second butyl. base, tert-butyl, pentyl, neopentyl, cyclopentyl, hexyl, cyclohexyl, 3-cyclohexenyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl base, pentadecyl, heptadecyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norbornyl, norbornylmethyl, tricyclodecyl, tetracyclodecyl Dialkyl, tetracyclododecylmethyl, dicyclohexylmethyl, eicosyl, allyl, benzyl, diphenylmethyl, tetrahydrofuranyl, methoxymethyl, ethoxymethyl group, methylthiomethyl, acetamidomethyl, trifluoroethyl, (2-methoxyethoxy)methyl, acetyloxymethyl, 2-carboxy-1-cyclohexyl, 2- Side oxypropyl, 4-side oxy-1-adamantyl, 3-side oxycyclohexyl, etc. In addition, a part of the hydrogen atoms of these groups can also be substituted with a group containing heteroatoms such as oxygen atom, sulfur atom, nitrogen atom, halogen atom, etc., or a part of the carbon atoms of these groups can also be inserted with oxygen atom, sulfur atom, etc. Atoms, nitrogen atoms and other heteroatoms may also contain hydroxyl, cyano, carbonyl, ether bond, ester bond, sulfonate bond, carbonate bond, lactone ring, sultone ring, carboxylic acid anhydride, halogen Alkyl etc.

For details on the synthesis of perylene salts having an anion represented by the formula (1A'), see JP 2007-145797 A, JP 2008-106045 A, JP 2009-7327 A, JP 2009-A Gazette No. 258695, etc. In addition, the salts described in JP 2010-215608 A, JP 2012-41320 A, JP 2012-106986 A, JP 2012-153644 A, and the like can also be preferably used.

Although the anion represented by Formula (1A) can be mentioned below, it is not limited to these. In addition, in the following formula, Ac is an acetyl group.

[Chemical 124]

[Chemical 126]

In formula (1B), R ^fb1 and R ^fb2 are each independently a fluorine atom, or a monovalent hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include the same monovalent hydrocarbon groups as those listed in the description of R ¹¹² above. R ^fb1 and R ^fb2 are preferably a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. In addition, R ^fb1 and R ^fb2 may be bonded to each other and form a ring together with the group to which they are bonded (-CF ₂ -SO ₂ -N ^- -SO ₂ -CF ₂ -), in this case, R ^fb1 and R ^fb2 The groups obtained by bonding with each other are particularly preferably fluorinated ethylidene and fluorinated propylidene.

In formula (1C), R ^fc1 , R ^fc2 and R ^fc3 are each independently a fluorine atom or a monovalent hydrocarbon group having 1 to 40 carbon atoms which may also contain a hetero atom. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include the same monovalent hydrocarbon groups as those listed in the description of R ¹¹² above. R ^fc1 , R ^fc2 and R ^fc3 are preferably a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. In addition, R ^fc1 and R ^fc2 may be bonded to each other and form a ring together with the group to which they are bonded (-CF ₂ -SO ₂ -C ^- -SO ₂ -CF ₂ -), in this case, R ^fc1 and R ^fc2 The groups obtained by bonding with each other are preferably those which form a ring structure with fluorinated ethylidene and fluorinated propylidene.

In formula (1D), R ^fd is a monovalent hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include the same monovalent hydrocarbon groups as those listed in the description of R ¹¹² above.

For the synthesis of the perylene salt having the anion represented by the formula (1D), see Japanese Patent Laid-Open No. 2010-215608 and Japanese Patent Laid-Open No. 2014-133723 for details.

The anion represented by the formula (1D) includes, but is not limited to, those shown below.

In addition, the photoacid generator having the anion represented by the formula (1D) does not have fluorine at the α-position of the sulfo group, but has two trifluoromethyl groups at the β-position, so it has sufficient acidity to prevent photoresist Acid-labile groups in the polymer are cleaved. Therefore, it can be used as a photoacid generator.

Moreover, it is also preferable that the photoacid generator of the component (D) is represented by the following formula (2).

In formula (2), R ²⁰¹ and R ²⁰² are each independently a monovalent hydrocarbon group having 1 to 30 carbon atoms which may also contain a hetero atom. R ²⁰³ is a divalent hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom. Moreover, any two of R ²⁰¹ , R ²⁰² and R ²⁰³ may be bonded to each other and form a ring together with the sulfur atom to which they are bonded. L ^A is a single bond, an ether bond, or a divalent hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom. X ^a , X ^b , X ^c and X ^d are each independently a hydrogen atom, a fluorine atom or a trifluoromethyl group. However, at least one of X ^a , X ^b , X ^c and X ^d is a fluorine atom or a trifluoromethyl group.

The monovalent hydrocarbon group represented by R ²⁰¹ and R ²⁰² may be linear, branched, or cyclic, and specific examples thereof include methyl, ethyl, propyl, isopropyl, n-butyl, 2-butyl, 3-butyl, 3-pentyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, cyclopentyl, cyclohexyl, 2-ethylhexyl, cyclopentyl Methyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, oxanorbornyl, tricyclic [5.2.1.0 ^2,6 ] Decyl, adamantyl, phenyl, naphthyl, anthracenyl, etc. In addition, a part of the hydrogen atoms of these groups can also be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and oxygen atoms, sulfur atoms, The group of heteroatoms such as nitrogen atom may, as a result, also contain a hydroxyl group, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride, and a haloalkyl group. Wait.

Examples of the divalent hydrocarbon group represented by R ²⁰³ include methylene, ethylidene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, and hexane- 1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane -1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl Alkanediyl, hexadecane-1,16-diyl, heptadecan-1,17-diyl and other linear alkanediyl; cyclopentanediyl, cyclohexanediyl, norbornanediyl, diamond Divalent saturated cyclic hydrocarbon groups such as alkanediyl; aryl extensions such as phenylene, naphthyl, etc. In addition, a part of the hydrogen atoms of these groups may be substituted with alkyl groups such as methyl, ethyl, propyl, n-butyl, and tert-butyl. In addition, a part of the hydrogen atoms of these groups can also be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and oxygen atoms, sulfur atoms, The group of heteroatoms such as nitrogen atom may, as a result, also contain a hydroxyl group, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic acid anhydride, and a haloalkyl group. Wait. The aforementioned heteroatom is preferably an oxygen atom.

The photoacid generator represented by the formula (2) is preferably represented by the following formula (2').

In formula (2'), L ^A is the same as described above. X ^e is a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. R ³⁰¹ , R ³⁰² and R ³⁰³ are each independently a hydrogen atom, or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include the same monovalent hydrocarbon groups as those listed in the description of R ¹¹² above. p and q are each independently an integer of 0 to 5, and r is an integer of 0 to 4.

The photoacid generator represented by the formula (2) includes, but is not limited to, those shown below. In addition, in the following formula, X ^e is the same as described above, and Me is a methyl group.

[Chemical 131]

Among the other photoacid generators mentioned above, those containing the anion represented by the formula (1A') or (1D) have small acid diffusion and are also excellent in solubility in photoresist solvents, which are particularly preferred. In addition, those containing the anion represented by the formula (2') have extremely small acid diffusion and are particularly preferred.

When the photoacid generator of (D) component is contained, its content is preferably 0.1-40 mass parts with respect to 80 mass parts of (B) base resins, More preferably, it is 0.5-20 mass parts. When the addition amount of the photoacid generator of the component (D) is in the above-mentioned range, the resolution is good, and there is no possibility of a foreign matter problem after development or peeling of the photoresist film, which is preferable. (D) The photoacid generator of a component can be used individually by 1 type or in combination of 2 or more types.

[(E) quencher]

The chemically amplified photoresist composition of the present invention may further contain a quencher (acid diffusion control agent). Further, in the present invention, the quencher refers to a material for forming a desired pattern by capturing the acid generated by the photoacid generator in the chemically amplified photoresist composition, preventing its diffusion to the unexposed portion.

(E) The quencher includes onium salts represented by the following formula (3) or (4).

In formula (3), R ^q1 is a hydrogen atom, or a monovalent hydrocarbon group having 1 to 40 carbon atoms that may also contain a hetero atom, but the hydrogen atom bound to the carbon atom at the α position of the sulfo group is through a fluorine atom or a fluorocarbon. Except for base substitutions. In formula (4), R ^q2 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 40 carbon atoms which may also contain a hetero atom. The monovalent hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include the same monovalent hydrocarbon groups as those exemplified in the description of R ¹¹² in the formula (1A′).

Specific examples of the monovalent hydrocarbon group represented by R ^q1 include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, Third pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, cyclopentyl, cyclohexyl, 2-ethylhexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl , cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, oxanorbornyl, tricyclo[5.2.1.0 ^2,6 ]decyl, adamantyl, phenyl, naphthyl, anthracene Base et al. In addition, a part of the hydrogen atoms of these groups can also be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., or the carbon atoms of these groups can also be inserted with oxygen atoms, sulfur atoms, etc. , nitrogen atom and other heteroatom groups, the result may also contain hydroxyl, cyano, carbonyl, ether bond, ester bond, sulfonate bond, carbonate bond, lactone ring, sultone ring, carboxylic anhydride, haloalkane Base et al.

Specific examples of the monovalent hydrocarbon group represented by R ^q2 include, in addition to the substituents exemplified as specific examples of R ^q1 , fluorinated alkyl groups such as trifluoromethyl and trifluoroethyl, and pentafluorobenzene. fluorinated aryl groups, such as 4-trifluoromethylphenyl, etc.

The anions of the onium salt represented by the formula (3) include, but are not limited to, those shown below.

[Chemical 136]

The anions of the onium salt represented by the formula (4) include, but are not limited to, those shown below.

[Chemical 137]

In formulas (3) and (4), Mq ⁺ is an onium cation. The aforementioned onium cation is preferably represented by the following formula (5a), (5b) or (5c).

[Chemical 138]

In formulae (5a) to (5c), R ^q11 to R ^q19 are each independently a monovalent hydrocarbon group having 1 to 40 carbon atoms which may also contain a hetero atom. Also, R ^q11 and R ^q12 may be bonded to each other and form a ring together with the sulfur atom to which they are bonded, and R ^q16 and R ^q17 may be bonded to each other and form a ring together with the nitrogen atom to which they are bonded. Examples of the above-mentioned monovalent hydrocarbon group include the same monovalent hydrocarbon groups as described in the description of R ^q1 in the formula (3).

The onium cation represented by Mq ⁺ includes, but is not limited to, those shown below. In addition, in the following formula, Me is a methyl group.

[Chemical 139]

Specific examples of the onium salt represented by the formula (3) or (4) include any combination of the aforementioned anions and cations. In addition, these onium salts can be easily prepared by ion exchange reaction using known organic chemical methods. Regarding the ion exchange reaction, for example, Japanese Patent Laid-Open No. 2007-145797 can be referred to.

The onium salt represented by the formula (3) or (4) functions as a quencher in the chemically amplified photoresist composition of the present invention. This is because the opposite anions of the aforementioned onium salts are conjugate bases of weak acids. The weak acid as used herein refers to an acidity that cannot deprotect the acid-labile group of the acid-labile group-containing unit used in the base resin. The onium salt represented by the formula (3) or (4) functions as a quencher when used together with an onium salt-type photoacid generator having a conjugate base of a strong acid such as a fluorinated sulfonic acid at the α position as a counter anion. Function. That is, when an onium salt that produces a strong acid such as a fluorinated sulfonic acid at the α position is used in combination with an onium salt that produces a weak acid such as a sulfonic acid and a carboxylic acid that is not substituted by fluorine, it is irradiated with high-energy rays from light. If the strong acid generated by the acid generator collides with the unreacted onium salt with a weak acid anion, the weak acid will be released due to salt exchange, and a strong acid anion will be generated. Onium salt. In this process, the strong acid is exchanged into a weak acid with lower catalytic capacity, so the acid is apparently inactivated and the acid diffusion can be controlled.

Here, when the photoacid generator that generates the strong acid is an onium salt, as described above, the strong acid generated by irradiation with high-energy rays can be exchanged for the weak acid. The strong acid-producing onium salts of the reaction collide to exchange salts. It is due to the phenomenon that onium cations easily form ion pairs with anions of stronger acids.

When the onium salt represented by the formula (3) or (4) is contained as the (E) quencher, its content is preferably 0.1 to 10 parts by mass relative to 80 parts by mass of the (B) base resin, more preferably 0.1 to 5 parts by mass . When the quencher of the component (E) is in the above-mentioned range, the resolution is good and the sensitivity does not decrease significantly, which is preferable. The onium salt represented by the formula (3) or (4) may be used alone or in combination of two or more.

In addition, a nitrogen-containing compound can also be used as a quencher of (E) component. Examples of such nitrogen-containing compounds include the primary, secondary or tertiary amine compounds described in paragraphs [0146] to [0164] of JP-A No. 2008-111103, especially those having a hydroxyl group, an ether bond, an ester bond, an internal Amine compound of ester ring, cyano group and sulfonate bond. Moreover, like the compound described in Japanese Patent No. 3790649, the compound obtained by protecting a primary or secondary amine with a urethane group can also be mentioned.

In addition, as the nitrogen-containing compound, a sulfonic acid sulfonium salt having a nitrogen-containing substituent may be used. Such a compound functions as a quencher in the unexposed part, and the exposed part loses the ability of the quencher due to neutralization with the acid generated by itself, and functions as a so-called photodegradable base. By using a photodisintegrating alkali, the contrast of an exposed part and an unexposed part can be improved further. For example, the photodegradable base can be referred to Japanese Patent Laid-Open No. 2009-109595, Japanese Patent Laid-Open No. 2012-46501, and the like.

When the nitrogen-containing compound is contained as the quencher of the component (E), the content thereof is preferably 0.001 to 12 parts by mass, more preferably 0.01 to 8 parts by mass, relative to 80 parts by mass of the (B) base resin. The aforementioned nitrogen-containing compounds may be used alone or in combination of two or more.

[(F) Surfactant that is insoluble or sparingly soluble in water but soluble in alkali developer, and/or insoluble or sparingly soluble in water and alkali developer]

The chemically amplified photoresist composition of the present invention may further contain (F) a surfactant that is insoluble or poorly soluble in water but soluble in an alkaline developer, and/or an interface active agent that is insoluble or poorly soluble in water and an alkaline developer agent. For such surfactants, reference can be made to those described in Japanese Patent Application Laid-Open No. 2010-215608 and Japanese Patent Application Laid-Open No. 2011-16746.

Among the surfactants described in the aforementioned gazettes, FC-4430 (manufactured by 3M Corporation), surflon (registered trademark) S-381 (AGC SEIMI CHEMICAL (AGC SEIMI CHEMICAL) Co., Ltd.), OLFINE (registered trademark) E1004 (Nissin Chemical Industry Co., Ltd.), KH-20, KH-30 (AGC SEIMI CHEMICAL Co., Ltd.), and oxygen represented by the following formula (surf-1) Heterobutane ring-opening polymers, etc.

Here, R, Rf, A, B, C, m, and n are not limited to the above descriptions, and are only applicable to the formula (surf-1). R is a 2-4 valence aliphatic group having 2-5 carbon atoms. As the aforementioned aliphatic group, divalent ones include ethylidene, 1,4-hexylene As butyl group, 1,2-propylidene group, 2,2-dimethyl-1,3-propylidene group, 1,5-pentylene group, etc., the following ones are mentioned as trivalent or tetravalent ones.

In the formula, the dotted lines are atomic bonds, each of which is a substructure derived from glycerol, trimethylolethane, trimethylolpropane, and neopentaerythritol.

Among these, 1,4-butylene, 2,2-dimethyl-1,3-propylidene, and the like are preferable.

Rf is trifluoromethyl or pentafluoroethyl, preferably trifluoromethyl. m is an integer from 0 to 3, n is an integer from 1 to 4, and the sum of n and m is the valence of R, which is an integer from 2 to 4. A is 1. B is an integer from 2 to 25, preferably an integer from 4 to 20. C is an integer from 0 to 10, preferably 0 or 1. In addition, the arrangement|positioning of each structural unit in Formula (surf-1) is not prescribed|regulated, and it may couple|bond in a block or at random. For the manufacture of partially fluorinated oxetane ring-opening polymer-based surfactants, see the specification of US Pat. No. 5,650,483 and the like.

A surfactant that is insoluble or poorly soluble in water but soluble in an alkaline developer. When the photoresist protective film is not used in ArF immersion exposure, it can be aligned on the surface of the photoresist film and has the ability to penetrate and dissolve water. reduced functionality. Therefore, the elution of water-soluble components from the photoresist film is suppressed, which is useful for reducing damage to the exposure device. Furthermore, it becomes solubilized during development in an alkaline aqueous solution after exposure and post-exposure baking (PEB), and is less likely to become A foreign object that becomes the cause of a defect is useful. Such surfactants have the properties of being insoluble or insoluble in water but soluble in alkaline developing solutions. They are suitable for polymer surfactants, also known as hydrophobic resins, especially with high water repellency, which makes them more slidable. good.

As such a polymer-type surfactant, the thing containing at least 1 sort(s) chosen from the repeating unit represented by following formula (6A)-(6E) is mentioned.

In formulas (6A) to (6E), R ^B is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. W ¹ is -CH ₂ -, -CH ₂ CH ₂ -, -O-, or two -Hs separated from each other. R ^s1 is each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. R ^s2 is a single bond, or a linear or branched divalent hydrocarbon group having 1 to 5 carbon atoms. R ^s3 is each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 15 carbon atoms, a fluorinated monovalent hydrocarbon group, or an acid-labile group. When R ^s3 is a monovalent hydrocarbon group or a fluorinated monovalent hydrocarbon group, an ether bond (-O-) or a carbonyl group (-C(=O)-) may be inserted between the carbon-carbon bonds. R ^s4 is a (u+1)-valent hydrocarbon group or a fluorinated hydrocarbon group having 1 to 20 carbon atoms. u is an integer from 1 to 3. R ^s5 is each independently a hydrogen atom or a group represented by the formula -C(=O)-OR ^sa , and R ^sa is a fluorinated hydrocarbon group having 1 to 20 carbon atoms. R ^s6 is a monovalent hydrocarbon group with 1 to 15 carbon atoms or a fluorinated monovalent hydrocarbon group, and an ether bond (-O-) or a carbonyl group (-C(=O)-) can also be inserted between the carbon-carbon bonds.

The monovalent hydrocarbon group represented by R ^s1 may be linear, branched or cyclic, and specific examples thereof include methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl base, isobutyl, sec-butyl, tert-butyl, cyclobutyl, n-pentyl, cyclopentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, Adamantyl, norbornyl, etc. Among these, those having 1 to 6 carbon atoms are preferable.

The divalent hydrocarbon group represented by R ^s2 may be linear, branched, or cyclic, and specific examples thereof include a methylene group, an ethylidene group, a propylidene group, a butylene group, and a pentylene group.

The monovalent hydrocarbon group represented by R ^s3 or R ^s6 may be linear, branched, or cyclic, and specific examples thereof include an alkyl group, an alkenyl group, an alkynyl group, and the like, and an alkyl group is preferable. The above-mentioned alkyl group includes n-undecyl group, n-dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, and the like in addition to those exemplified as the monovalent hydrocarbon group represented by R ^s1 . Examples of the fluorinated monovalent hydrocarbon group represented by R ^s3 or R ^s6 include groups in which part or all of the hydrogen atoms bonded to the carbon atoms of the aforementioned monovalent hydrocarbon group are substituted with fluorine atoms. As mentioned above, these carbon-carbon bonds may also contain ether bonds (-O-) or carbonyl groups (-C(=O)-).

The acid-labile groups represented by R ^s3 can be listed as follows: the groups represented by the aforementioned formulas (L1)~(L4); carbon number 4~20, preferably a 3-level alkyl group with carbon number 4~15; each alkyl group is a carbon Trialkylsilyl with 1-6 alkyl groups; alkyl groups with 4-20 carbon atoms containing pendant oxygen groups, etc.

The (u+1)-valent hydrocarbon group or fluorinated hydrocarbon group represented by R ^s4 may be any one of linear, branched, and cyclic, and specific examples thereof include the above-mentioned monovalent hydrocarbon group or fluorinated monovalent hydrocarbon group and the like. A base obtained by removing u hydrogen atoms.

The fluorinated hydrocarbon group represented by R ^sa may be linear, branched, or cyclic, and specific examples thereof include those in which a part or all of the hydrogen atoms of the aforementioned monovalent hydrocarbon group are substituted with fluorine atoms, and specific examples include : Trifluoromethyl, 2,2,2-trifluoroethyl, 3,3,3-trifluoro-1-propyl, 3,3,3-trifluoro-2-propyl, 2,2,3 ,3-tetrafluoropropyl, 1,1,1,3,3,3-hexafluoroisopropyl, 2,2,3,3,4,4,4-heptafluorobutyl, 2,2,3 ,3,4,4,5,5-octafluoropentyl, 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl, 2-(all Fluorobutyl)ethyl, 2-(perfluorohexyl)ethyl, 2-(perfluorooctyl)ethyl, 2-(perfluorodecyl)ethyl, and the like.

The repeating units represented by the formulae (6A) to (6E) include, but are not limited to, those shown below. In addition, in the following formula, R ^B is the same as that mentioned above.

[Chemical 146]

[Chemical 148]

[Chemical 149]

The aforementioned polymeric surfactant may further contain other repeating units other than the repeating units represented by formulae (6A) to (6E). Other repeating units include repeating units derived from methacrylic acid, α-trifluoromethacrylic acid derivatives, and the like. In the polymer surfactant, the content of the repeating units represented by formulas (6A) to (6E) in all repeating units should preferably be 20 mol% or more, more preferably 60 mol% or more, and 100 mol%. better.

The Mw of the aforementioned polymeric surfactant is preferably 1,000-500,000, more preferably 3,000-100,000. Mw/Mn is preferably 1.0 to 2.0, more preferably 1.0 to 1.6.

烷等。聚合引發劑可列舉：AIBN、2,2’-偶氮雙(2,4-二甲基戊腈)、二甲基2,2-偶氮雙(2-甲基丙酸酯)、過氧化苯甲醯、過氧化月桂醯等。反應溫度宜為50~100℃。反應時間宜為4~24小時。酸不穩定基可直接使用已導入到單體者，也可於聚合後予以保護化或部分保護化。 As a method for synthesizing the aforementioned polymer-based surfactant, there may be exemplified the addition of free unsaturated bond-containing monomers that provide repeating units represented by the formulae (6A) to (6E) and other repeating units as needed in an organic solvent. base initiator and heating to carry out the polymerization method. The organic solvent used in the polymerization includes toluene, benzene, THF, diethyl ether, diethyl ether,

alkane etc. Examples of the polymerization initiator include AIBN, 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2-azobis(2-methylpropionate), peroxide Benzoic acid, lauric acid peroxide, etc. The reaction temperature is preferably 50 to 100°C. The reaction time is preferably 4 to 24 hours. The acid-labile group may be directly introduced into the monomer, or may be protected or partially protected after polymerization.

When synthesizing the aforementioned polymer surfactant, in order to adjust the molecular weight, a known chain transfer agent such as dodecyl mercaptan and 2-mercaptoethanol can also be used. At this time, the added amount of these chain transfer agents is preferably 0.01-10 mol% relative to the total moles of the monomers to be polymerized.

When the surfactant of the component (F) is contained, its content is preferably 0.1 to 50 parts by mass, more preferably 0.5 to 10 parts by mass, relative to 80 parts by mass of the (B) base resin. If the addition amount is 0.1 parts by mass or more, the receding contact angle between the surface of the photoresist film and water is sufficiently improved, and if it is less than 50 parts by mass, the dissolution rate of the surface of the photoresist film to the developer is low, and the height of the formed fine pattern is sufficient. Keep.

[(G) Other ingredients]

The chemically amplified photoresist composition of the present invention may also contain a compound that is decomposed by an acid to generate an acid (acid-proliferating compound), an organic acid derivative, an alcohol substituted with fluorine, and its solubility in a developer may be affected by the action of an acid. Compounds (dissolution inhibitors) with a changed Mw of 3,000 or less are used as (G) other components. aforementioned acid proliferation For the compound, refer to the compounds described in JP-A No. 2009-269953 or JP-A No. 2010-215608. When the aforementioned acid-proliferating compound is contained, the content thereof is preferably 0 to 5 parts by mass, more preferably 0 to 3 parts by mass, relative to 80 parts by mass of the (B) base resin. If the content is too large, it may be difficult to control the diffusion, and the analyzability may be deteriorated or the pattern shape may be deteriorated. As the organic acid derivative, the fluorine-substituted alcohol, and the dissolution inhibitor, the compounds described in JP-A-2009-269953 or JP-A-2010-215608 can be referred to.

[Pattern formation method]

The pattern forming method of the present invention comprises the following steps: forming a photoresist film on a substrate using the photoresist composition; exposing the photoresist film by KrF excimer laser light, ArF excimer laser light, EB or EUV; and using The developing solution develops the above-mentioned exposed photoresist film.

As the aforementioned substrate, for example, a substrate for manufacturing an integrated circuit (Si, SiO ₂ , SiN, SiON, TiN, WSi, BPSG, SOG, an organic antireflection film, etc.), or a substrate for manufacturing a mask circuit (Cr, CrO, CrON, MoSi ₂ , SiO ₂ , etc.).

As for the photoresist film, for example, the above-mentioned photoresist composition can be applied to a film thickness of 0.05 to 2 μm by a method such as spin coating. 10 minutes, more preferably, it is formed by pre-baking under the conditions of 80 to 140° C. and 1 to 5 minutes.

When KrF excimer laser light, ArF excimer laser light or EUV is used for the exposure of the photoresist film, a mask for forming the target pattern can be used, so that the exposure amount is preferably 1~200mJ/cm ² , more preferably The irradiation is carried out so as to be 10 to 100 mJ/cm ² . When EB is used, it is irradiated with a mask for forming a target pattern or directly so that the exposure amount is preferably 1 to 300 μC/cm ² , more preferably 10 to 200 μC/cm ² .

Moreover, in addition to the normal exposure method, the dipping method which inserts the liquid with a refractive index of 1.0 or more between a photoresist film and a projection lens can also be used for exposure. In this case, a water-insoluble protective film may also be used.

The said water-insoluble protective film is used in order to prevent the elution from a photoresist film and improve the water-sliding property of a film surface, and is roughly divided into two types. One of them is an organic solvent peeling type that needs to be peeled off with an organic solvent that does not dissolve the photoresist film before developing in an alkaline aqueous solution, and the other is an alkaline developing solution soluble, which removes the protective film at the same time as the soluble part of the photoresist film is removed. The alkali aqueous solution soluble type. The latter is particularly preferably based on a polymer having a 1,1,1,3,3,3-hexafluoro-2-propanol residue which is insoluble in water but soluble in an alkaline developer and soluble in a polymer having 4 or more carbon atoms. A material obtained from an alcohol-based solvent, an ether-based solvent having 8 to 12 carbon atoms, and a mixed solvent thereof. It can also be prepared by dissolving the aforementioned surfactant, which is insoluble in water but soluble in alkaline developer, in an alcohol solvent with a carbon number of 4 or more, an ether solvent with a carbon number of 8 to 12, or a mixed solvent thereof. .

PEB can also be performed after exposure. PEB can be implemented by, for example, heating on a hot plate at preferably 60 to 150° C. for 1 to 5 minutes, more preferably 80 to 140° C. for 1 to 3 minutes.

For development, for example, a developing solution of an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH) is preferably used in an amount of 0.1 to 5 mass %, more preferably 2 to 3 mass %, and is immersed by a dip method. It is preferable that it is 0.1 to 3 minutes, and it is more preferable that it is 0.5 to 2 minutes to develop a normal method, such as a puddle method and a spray method, and a target pattern is formed on a board|substrate.

In addition, in terms of the pattern formation method, after the photoresist film is formed, a pure water postsoak may be performed to extract an acid generator or the like from the film surface, or particles may be washed away, or it may be performed after exposure. A postsoak to remove residual water on the membrane.

In addition, a pattern can also be formed by a double patterning method. The two-pattern method can be exemplified: the trench method, which uses the first exposure and etching to process the substrate of the 1:3 trench pattern, shifts the position and forms a 1:3 trench pattern with the second exposure, and forms a 1:1 trench pattern. Pattern; line method, using the first exposure and etching to process the first substrate with a 1:3 isolated residual pattern, shifting the position and using the second exposure to form a 1:3 isolated residual pattern under the first substrate The second substrate is processed to form a 1:1 pattern of half pitch.

In the pattern forming method of the present invention, a negative-tone development method of dissolving and developing the unexposed portion using an organic solvent may be used instead of the developing solution of the aforementioned alkaline aqueous solution as the developing solution.

In the organic solvent development, the developer can use: 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl Ketone, methylcyclohexanone, acetophenone, methylacetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butenyl acetate, isoamyl acetate, propyl formate, formic acid Butyl, isobutyl formate, amyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl crotonate, ethyl crotonate, methyl propionate, ethyl propionate, 3- Ethoxy propionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, amyl lactate, isoamyl lactate, methyl 2-hydroxyisobutyrate, 2-hydroxyl Ethyl isobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, phenyl methyl acetate, benzyl formate, phenyl ethyl formate, methyl 3-phenyl propionate, propyl Benzyl acetate, ethyl phenylacetate, 2-phenylethyl acetate, etc. These organic solvents may be used alone or in combination of two or more.

[Example]

Hereinafter, the present invention will be specifically described with reference to Synthesis Examples, Examples and Comparative Examples, but the present invention is not limited to the following Examples. In addition, the apparatuses used are as follows.

. IR: Thermo Fisher Scientific, NICOLET 6700

. ¹ H-NMR: ECA-500 manufactured by JEOL Ltd.

. LC-MS: Waters Corporation, ACQUITY UPLC H-Class System and ACQUITY QDa

[1] Synthesis of peronium compounds

[Example 1-1] Synthesis of PAG-1

[Example 1-1-1] Synthesis of Intermediate 1

In a nitrogen atmosphere, raw material 1 (225 g), raw material 2 (182 g), and copper iodide (1) (4.4 g) were dissolved in N-methylpyrrolidone (700 g) in a flask, and heated to 70°C. Then, triethylamine (102g) was dripped, and it aged at 80 degreeC for 24 hours. After confirming the disappearance of the raw material 1 by GC, the reaction system was cooled, and water (1,000 g) was added dropwise to stop the reaction. After that, it was extracted with toluene (2,000 mL), subjected to ordinary aqueous work-up, and the solvent was distilled off, followed by recrystallization with hexane to obtain Intermediate 1 as white crystals (yield 233 g, yield 90 %).

[Example 1-1-2] Synthesis of Intermediate 2

Under a nitrogen atmosphere, Intermediate 1 (119 g) and acetic acid (500 g) were added to the flask and dissolved at 30°C. Then, 35 mass % hydrogen peroxide water (41g) was dripped in the state which maintained 40 degrees C or less. After the dropwise addition, it was aged at 40°C for 20 hours. After aging, the reaction system was cooled, and a solution consisting of sodium thiosulfate pentahydrate (20 g) and water (400 g) was added dropwise to stop the reaction. Then, toluene (1,300 mL) and ethyl acetate (300 mL) were added to extract the target substance, and after performing ordinary aqueous work-up to remove the solvent, recrystallization was performed with hexane to obtain white crystals. Intermediate 2 (yield 115 g, 92% yield).

[Example 1-1-3] Synthesis of Intermediate 3

Under nitrogen atmosphere, intermediate 2 (15.6 g), p-toluenesulfonic acid monohydrate (1.0 g), raw material 3 (15.2 g), and toluene (70 g) were added to the flask, and heated under reflux at 105° C. for 7 hours. The disappearance of Intermediate 2 was confirmed by TLC, and the reaction solution was ice-cooled, and then triethylamine (1.0 g) was added to stop the reaction. Separately, a saturated aqueous solution of sodium bicarbonate (50 mL) was added, the target product was extracted with toluene (50 mL), and after performing ordinary aqueous work-up and distilling off the solvent, purification was performed by silica gel column chromatography (elution). Liquid: hexane/ethyl acetate=15/1), Intermediate 3 was obtained as a colorless oily substance (yield 21.8 g, yield 98%).

[Example 1-1-4] Synthesis of Intermediate 4

Grignard's reagent was prepared in a flask from 4-bromofluorobenzene (26.8 g), metallic magnesium (3.7 g) and THF (60 g) under nitrogen. After preparation, the reaction system was cooled, and a solution consisting of Intermediate 3 (21.8 g) and THF (25 g) was added. Then, trimethylchlorosilane (16.6 g) was added dropwise at 20° C. or lower, and the mixture was aged in an ice bath for 2 hours. After the aging, while cooling the reaction system, a saturated aqueous ammonium chloride solution (100 mL) was added dropwise to stop the reaction. Extracted with methyl isobutyl ketone (150 mL), carried out ordinary aqueous work-up and distilled off the solvent, and then recrystallized with hexane to obtain Intermediate 4 (yield: 28.3 g, 28.3 g) as white crystals. yield 94%).

[Example 1-1-5] Synthesis of Intermediate 5

Under nitrogen atmosphere, intermediate 4 (14.2 g), 1,1-difluoro-2-hydroxyethane-1-sulfonic acid benzyltrimethylammonium (9.0 g), methyl isobutyl ketone (70 g ) and water (50 g) were added to the flask, and after stirring for 30 minutes, the organic layer was separated and washed with water, and then concentrated under reduced pressure. Hexane was added to the concentrated solution and washed, whereby Intermediate 5 was obtained as an oily substance (yield 15.2 g, yield 94%).

[Example 1-1-6] Synthesis of PAG-1

Under a nitrogen atmosphere, sodium hydride (0.6 g) was suspended in THF (56 g), and the reaction system was cooled. A solution consisting of Intermediate 5 (7.9 g) and THF (55.5 g) was added dropwise below 5°C. Then, it aged at room temperature for 12 hours. After aging, the reaction system was cooled, and water (60 mL) was added dropwise to stop the reaction. Extracted with methyl isobutyl ketone (150 g), carried out ordinary aqueous work-up and distilled off the solvent, and then recrystallized with hexane to obtain PAG-1 (yield: 7.1 g, 7.1 g, yield) of white crystals. yield 92%).

The IR spectral data of PAG-1 and the results of LC-MS are shown below. Moreover, the result of the nuclear magnetic resonance spectrum ( ¹ H-NMR/DMSO-d ₆ ) is shown in FIG. 1 .

IR(D-ATR): ν=3484, 3094, 2963, 2872, 1589, 1494, 1397, 1368, 1316, 1259, 1237, 1180, 1152, 1110, 1068, 1035, 989, 932, 879, 833, 779 , 689, 667, 649, 635, 619, 591, 552, 524 cm ^-1 .

LC-MS: POSITIVE[M+H] ⁺ 649

[Example 1-2] Synthesis of PAG-2

Except having used raw material 4 instead of raw material 3, PAG-2 was obtained in the same manner as in Example 1-1 (yield 5.0 g, yield 94% in the final step).

The IR spectral data and LC-MS results of PAG-2 are shown below. Moreover, the result of the nuclear magnetic resonance spectrum ( ¹ H-NMR/DMSO-d ₆ ) is shown in FIG. 2 .

IR(D-ATR): ν=3492, 3064, 2963, 2870, 1589, 1494, 1398, 1365, 1317, 1256, 1237, 1215, 1181, 1125, 1104, 1078, 1034, 1009, 988, 949, 914 , 876, 834, 777, 743, 726, 670, 651, 635, 619, 590, 552, 524cm ^-1 .

LC-MS: POSITIVE[M+H] ⁺ 607

[Example 1-3] Synthesis of PAG-3

[hua 152]

Except having used the raw material 5 instead of the raw material 3, PAG-3 was obtained by the same method as Example 1-1 (yield 4.3 g, the yield of the final step 95%).

The results of LC-MS of PAG-3 are shown below.

LC-MS: POSITIVE[M ⁺ H]+579

[Example 1-4] Synthesis of PAG-4

Except having used raw material 6 instead of raw material 3, PAG-4 was obtained in the same manner as in Example 1-1 (yield 8.4 g, final step yield 78%).

The IR spectral data and LC-MS results of PAG-4 are shown below. Moreover, the result of the nuclear magnetic resonance spectrum ( ¹ H-NMR/DMSO-d ₆ ) is shown in FIG. 3 .

IR(D-ATR): ν=3488, 3096, 2961, 2873, 1589, 1494, 1454, 1399, 1315, 1261, 1236, 1172, 1135, 1115, 1073, 1032, 1009, 989, 935, 834, 778 , 712, 678, 651, 636, 620, 591, 573, 545, 524cm ^-1 .

LC-MS: POSITIVE[M+H] ⁺ 665

[Example 1-5] Synthesis of PAG-5

[Example 1-5-1] Synthesis of Intermediate 6

Intermediate 6 was synthesized in the same manner as in Examples 1-1-1 to 1-1-2, except that the raw material 7 was used instead of the raw material 2.

[Example 1-5-2] Synthesis of Intermediate 7

Intermediate 7 was synthesized in the same manner as in Example 1-1-3 except that the starting material 8 was used instead of the starting material 3.

[Example 1-5-3] Synthesis of PAG-5

Use of 1,1,3,3,3-Pentafluoro-2-hydroxypropane-1-sulfonic acid benzyltrimethylammonium instead of 1,1-difluoro-2-hydroxyethane-1-sulfonic acid benzyltrimethylammonium PAG-5 was synthesized in the same manner as in Examples 1-1-4 to 1-1-6 except that methylammonium was used.

The IR spectral data and LC-MS results of PAG-5 are shown below. Moreover, the result of the nuclear magnetic resonance spectrum ( ¹ H-NMR/DMSO-d ₆ ) is shown in FIG. 4 .

IR(D-ATR): ν=3486, 3097, 2976, 1587, 1493, 1448, 1401, 1369, 1318, 1245, 1161, 1107, 1087, 1060, 1012, 998, 913, 884, 834, 751, 741 , 690, 642, 593, 553, 525cm ^-1 .

LC-MS: POSITIVE[M ⁺ H]+713

[Examples 1-6~1-11] Synthesis of other PAGs (PAG-6~PAG-11)

[Chemical 155]

PAG-6 to PAG-11 were synthesized using the corresponding raw materials and known organic synthesis methods.

[2] Synthesis of polymers

The base resin used for the photoresist composition was synthesized by the method shown below. In addition, the weight average molecular weight (Mw) of the obtained polymer was measured as a polystyrene conversion value by GPC using THF as a solvent.

[Synthesis Example 1] Synthesis of Polymer P-1

Under a nitrogen atmosphere, 5.0 g of 3-hydroxy-1-adamantyl methacrylate, 14.4 g of α-methacryloyloxy-γ-butyrolactone, and 1-isopropyl methacrylate were taken in a flask. Amyl ester 20.8g, V-601 (Wako Pure Chemical Industries (stock) 0.49 g, 0.41 g of 2-mercaptoethanol, and 56 g of propylene glycol monomethyl ether acetate (PGMEA) to prepare a monomer-polymerization initiator solution. After adding 19 g of PGMEA to a flask in a separate nitrogen atmosphere, and heating to 80° C. with stirring, the aforementioned monomer-polymerization initiator solution was added dropwise over 4 hours. After the dropwise addition was completed, stirring was continued for 2 hours while the temperature of the polymerization solution was kept at 80° C., and then cooled to room temperature. The obtained polymer was added dropwise to 640 g of vigorously stirred methanol, and the precipitated polymer was analyzed by filtration. The obtained polymer was washed twice with 240 g of methanol, and then vacuum-dried at 50° C. for 20 hours to obtain a white powdery polymer P-1 (yield 35.3 g, yield 88%). As a result of analysis by GPC, the Mw of the polymer P-1 was 8,500, and the Mw/Mn was 1.58.

[Synthesis example 2~6] Synthesis of polymers P-2~P-6

The polymers P-2 to P-6 shown below were synthesized in the same manner as in Synthesis Example 1, except that the types and blending ratios of the monomers were changed.

[Chemical 158]

[3] Preparation of photoresist composition

[Examples 2-1 to 2-44, Comparative Examples 1-1 to 1-18]

The perionium compounds of the present invention (PAG-1~PAG-11), comparative photoacid generators (PAG-A~PAG-E), polymers (P-1~P-6), and other photoacid generators ( PAG-X, PAG-Y), quencher (Q-1~Q-4) and alkali-soluble surfactant SF-1, according to the composition shown in Tables 1~3 below, dissolved in surfactant A containing A photoresist composition was prepared by preparing a solution in a solvent of 0.01 mass % (manufactured by Omnova Co., Ltd.), and filtering the solution with a filter made of Teflon (registered trademark) having a size of 0.2 μm.

[Table 1]

[Table 2]

[table 3]

In addition, in Tables 1 to 3, solvents, other photoacid generators (PAG-X, PAG-Y), comparative photoacid generators (PAG-A to PAG-E), quenchers (Q-1 to Q -4), the alkali-soluble surfactant SF-1, and the surfactant A are as follows.

. Solvent: PGMEA (propylene glycol monomethyl ether acetate)

GBL (gamma-butyrolactone)

DAA (Diacetone Alcohol)

． Other photoacid generators: PAG-X, PAG-Y

． Comparative photoacid generators: PAG-A~PAG-E

． Quencher: Q-1~Q-4

[Chemical 164]

． Alkali-soluble surfactant SF-1:

Poly(2,2,3,3,4,4,4-heptafluoro-1-isobutyl-1-butyl methacrylate. 9-(2,2,2-trifluoro-1-methacrylate) Trifluoroethyloxycarbonyl)-4-oxatricyclo[4.2.1.0 ^3,7 ]nonan-5-one-2-ester)

Mw=7,700, Mw/Mn=1.82

. Surfactant A:

3-Methyl-3-(2,2,2-trifluoroethoxymethyl)oxetane. Tetrahydrofuran. 2,2-Dimethyl-1,3-propanediol copolymer (manufactured by Omnova)

a: (b+b'): (c+c')=1: 4~7: 0.01~1 (Mole ratio)

Mw=1,500

[4] Evaluation of photoresist composition: Evaluation of ArF exposure patterning (1)

[Examples 3-1 to 3-17, Comparative Examples 2-1 to 2-5]

An anti-reflection film solution (ARC29A manufactured by Nissan Chemical Industry Co., Ltd.) was coated on a silicon substrate, and baked at 200° C. for 60 seconds to form an anti-reflection film (film thickness 100 nm). Spin-coat each photoresist composition (R-01~R-17, R-45~R-49) on the aforementioned anti-reflection film, bake at 100°C for 60 seconds with a heating plate, and prepare a photoresist film with a film thickness of 90nm . Using an ArF excimer laser scanning exposure machine (NSR-S610C manufactured by Nikon Corporation, NA=1.30, dipole, Cr mask), the exposure amount and focus were changed (exposure amount pitch: 1 mJ/cm ² , A line and space pattern (LS pattern) with a line width of 40 nm and a pitch of 80 nm on the wafer was subjected to immersion exposure while focusing pitch: 0.025 μm), and PEB was performed at the temperature shown in Table 4 for 60 seconds after exposure. In addition, water was used as the infiltration liquid. Then, immersion development was performed for 30 seconds with a 2.38 mass % TMAH aqueous solution, rinsed with pure water, and spin-dried to obtain a positive pattern. The LS pattern after development was observed with a length-measuring SEM (CG4000) manufactured by Hitachi High-Technologies Co., Ltd., and the sensitivity, exposure margin (EL), mask error factor (MEF), and line width roughness (LWR) were evaluated according to the following methods. and defect density. The results are shown in Table 4.

[Sensitivity evaluation]

In terms of sensitivity, the optimum exposure amount E _op (mJ/cm ² ) for obtaining an LS pattern with a line width of 40 nm and a pitch of 80 nm was obtained. The smaller the value, the higher the sensitivity.

[EL evaluation]

EL (unit: %) was calculated|required by the following formula from the exposure amount formed in the range of ±10% (36-44 nm) of the pitch width of 40 nm in the said LS pattern.

EL(%)=(｜E ₁ -E ₂ ｜/E _op )×100

E ₁ : Optimum exposure amount for forming an LS pattern with a line width of 36 nm and a pitch of 80 nm

E ₂ : Optimum exposure amount for forming an LS pattern with a line width of 44 nm and a pitch of 80 nm

E _op : Optimum exposure for forming an LS pattern with a line width of 40 nm and a pitch of 80 nm

[MEF Evaluation]

A fixed pitch, change the line width of the mask, and observe the line width of each pattern obtained by irradiating with E _op . From the change of the line width of the mask and the line width of the pattern, the value of MEF is obtained according to the following formula. The closer the value is to 1, the better the performance.

MEF=(Line width of pattern/Line width of mask)-b

b: constant

[LWR evaluation]

The dimension of the LS pattern obtained by irradiation with E _op was measured at 10 points in the longitudinal direction of the line, and from the result, the triple value (3σ) of the standard deviation (σ) was obtained as LWR. The smaller the value, the more uniform a pattern with small roughness and line width will be obtained.

[Defect Density Evaluation]

The number of defects in the pattern formed after development was inspected with a defect inspection apparatus KLA2800 (manufactured by KLA-Tencor), and the defect density was determined according to the following formula.

Defect density (pieces/cm ² ) = total number of defects detected/inspection area

Pattern formed: 1:1 line and space repeating pattern at 50nm

Defect inspection conditions: light source UV, inspection pixel size 0.28μm, cell to cell mode

In this evaluation, good: less than 0.05 pieces/cm ² ; bad: 0.05 pieces/cm ² or more.

As can be seen from the results shown in Table 4, the chemically amplified photoresist composition containing the peronium compound of the present invention as a photoacid generator has good sensitivity, and is also excellent in EL, MEF, and LWR. Moreover, it turned out that it is effective also for reducing image development defects. Therefore, it is ideal as an ArF wet lithography material.

[5] Evaluation of photoresist composition: Evaluation of ArF exposure patterning (2)

[Examples 4-1 to 4-19, Comparative Examples 3-1 to 3-5]

Each photoresist composition (R-18~R-36, R-50~R-54) was spin-coated on the spin-coated carbon film ODL-180 (carbon content of 80% by mass) on a substrate for three-layer processing on which a silicon-containing spin-on hard mask SHB-A941 (silicon content of 43% by mass) with a film thickness of 35nm has been formed, using heating The board was baked at 100°C for 60 seconds to form a photoresist film with a thickness of 100nm. It was exposed to an ArF excimer laser immersion scanning exposure machine (NSR-S610C manufactured by Nikon Corporation, NA=1.30, σ0.90/0.72, cross-pole opening 35 degrees, Azimuthally polarized illumination, 6% half-order phase shift) Mask, cross-pole illumination), while changing the exposure amount and focus (exposure amount pitch: 1mJ/cm ² , focus pitch: 0.025μm), a contact hole pattern with a size of 45nm and a pitch of 110nm on the wafer (CH pattern), and after exposure, PEB was performed at the temperatures shown in Table 5 for 60 seconds. In addition, water was used as the infiltration liquid. Then, immersion development was performed for 30 seconds with n-butyl acetate, rinsed with 4-methyl-2-pentanol, and spin-dried to obtain a negative pattern. The CH pattern after development was observed with a length measuring SEM (CG4000) manufactured by Hitachi High-Technologies Co., Ltd., and the sensitivity, MEF, dimensional uniformity (CDU) and depth of focus (DOF) were evaluated according to the following methods. The results are shown in Table 5.

[Sensitivity evaluation]

In terms of sensitivity, the optimum exposure amount E _op (mJ/cm ² ) for obtaining a CH pattern with a hole size of 45 nm and a pitch of 110 nm was determined. The smaller the value, the higher the sensitivity.

[MEF evaluation]

The pitch was fixed, the size of the mask was changed, and each CH pattern obtained by irradiation with E _op was observed. From the change in the size of the mask and the size of the CH pattern, the value of MEF is obtained according to the following formula. The closer the value is to 1, the better the performance.

MEF=(size of pattern/size of mask)-b

b: constant

[CDU evaluation]

For the CH pattern irradiated with E _op , the dimensions of 10 locations (9 CH patterns per location) in the same exposure shot were measured, and the triple value (3σ) of the standard deviation (σ) was obtained from the results. as a CDU. The smaller the value, the more excellent the dimensional uniformity of the CH pattern.

[DOF Evaluation]

The focus range formed in the range of ±10% (41 to 49 nm) of the size of 45 nm in the aforementioned CH pattern was obtained. The larger the value, the wider the depth of focus.

[Residual film rate evaluation]

The cross section of the CH pattern obtained by _Eop irradiation was observed with a length measuring SEM (S-4800) manufactured by Hitachi High-Technologies Co., Ltd., and the film thickness with respect to the film thickness after spin coating of 100 nm was determined as the residual film ratio. The larger the value, the more excellent the residual film ratio.

[table 5]

From the results shown in Table 5, it can be seen that the chemically amplified photoresist composition containing the perium compound of the present invention as a photoacid generator has good sensitivity even in negative pattern formation by organic solvent development, and is excellent in CDU, MEF, and DOF. . In addition, it was found that the residual film ratio was also excellent. As can be seen from the above, the photoresist composition of the present invention is also useful in organic solvent development treatment.

[6] Evaluation of photoresist composition: EB drawing evaluation

[Examples 5-1 to 5-8, Comparative Examples 4-1 to 4-8]

An anti-reflection film solution (DUV-42 manufactured by Nissan Chemical Industry Co., Ltd.) was coated on a silicon substrate, and baked at 200° C. for 60 seconds to form an anti-reflection film (film thickness 61 nm). Spin-coat each photoresist composition (R-37~R-44, R-55~R-62) on the aforementioned anti-reflection film, bake at 100°C for 60 seconds with a heating plate, and prepare a photoresist film with a film thickness of 45nm . Using the EB drawing device ELS-F125 (accelerating voltage 125kV) manufactured by ELIONIX, a contact hole with a size of 24 nm and a pitch of 48 nm was formed on the wafer while changing the exposure amount from 50 μC/cm ² in steps of 5 μC/cm ² . For the drawing of the pattern (CH pattern), after exposure, PEB was performed at the temperature shown in Table 6 for 60 seconds. Then, immersion development was performed for 30 seconds with a 2.38 mass % TMAH aqueous solution, rinsed with pure water, and spin-dried to obtain a positive pattern. The CH pattern after development was observed with a length-measuring SEM (S-9380) manufactured by Hitachi High-Technologies Co., Ltd., and the sensitivity, EL, and CDU were evaluated by the following methods. The results are shown in Table 6.

[Sensitivity evaluation]

In terms of sensitivity, the optimum exposure amount E _op (μC/cm ² ) for obtaining a CH pattern with a hole size of 24 nm and a pitch of 48 nm was determined. The smaller the value, the higher the sensitivity.

[EL evaluation]

From the exposure amount formed in the range of ±10% (21.6 to 26.4 nm) of the hole size of 24 nm in the aforementioned CH pattern, EL (unit: %) was obtained according to the following formula.

EL(%)=(｜E ₁ -E ₂ ｜/E _op )×100

E ₁ : Optimum exposure amount for forming a CH pattern with a hole size of 21.6 nm and a pitch of 48 nm

E ₂ : Optimum exposure amount for forming a CH pattern with a hole size of 26.4 nm and a pitch of 48 nm

E _op : The optimum exposure amount for forming a CH pattern with a hole size of 24 nm and a pitch of 48 nm

[CDU evaluation]

For the CH pattern irradiated with E _op , the dimensions of 10 locations (9 CH patterns per location) in the same exposure batch were measured, and from the results, three times the standard deviation (σ) (3σ) was obtained as CDU. The smaller the value, the more excellent the dimensional uniformity of the CH pattern.

From the results shown in Table 6, it can be seen that the chemically amplified photoresist composition containing the perionate compound of the present invention as a photoacid generator has good sensitivity, excellent EL and CDU, and is suitable as an EB lithography material and an EUV lithography material.

Claims (20)

A peronium compound represented by the following formula (A);

In the formula, Q ¹ and Q ² are each independently a fluorine atom or a fluorinated alkyl group with 1 to 6 carbon atoms; Q ³ and Q ⁴ are each independently a hydrogen atom, a fluorine atom or a fluorinated alkyl group with 1 to 6 carbon atoms. base; a is an integer of 1 to 4; b is 1 or 2; c is an integer of 0 to 3; L ^a1 to L ^a4 are each independently a single bond, an ether bond, an ester bond, a sulfonate bond, and a carbonate bond or a urethane bond; ^XL1 and ^XL2 are each independently a single bond, or a divalent hydrocarbon group with a carbon number of 2 to 40 that may contain heteroatoms; R ^a is a hydrogen atom, or may also contain a halogen atom or Monovalent hydrocarbon group with 1 to 20 carbon atoms of oxygen atom; R ^b and R ^c and adjacent oxygen atoms together form an acyclic acetal structure or a cyclic acetal structure, the acyclic acetal structure or cyclic acetal The structure is selected from at least one of the group consisting of the following structures;

R ¹ is a (a+1)-valent hydrocarbon group with 1 to 50 carbon atoms that can also contain heteroatoms; R ² is a monovalent hydrocarbon group that can also contain heteroatoms with 1 to 50 carbon atoms; R ³ can also contain heteroatoms A divalent hydrocarbon group with 1 to 50 carbon atoms; and, when b=1, R ¹ and R ² or R ² and R ³ can also bond with each other and form a ring together with the sulfur atom to which they bond, b=2 At the same time, R ¹ and R ³ or two R ¹ can also be bonded to each other and form a ring together with the sulfur atom to which they are bonded. As claimed in claim 1, the perionium compound is represented by the following formula (A-1);

In the formula, Q ¹ ~Q ⁴ , L ^a1 ~ ^{L a4} , XL1 , ^XL2 , R ^a , R ^b , R ^c , R ² , R ³ , a, b and c are the same as above; R ^d can be Monovalent hydrocarbon group with 1 to 20 carbon atoms containing heteroatoms; d is an integer satisfying 0≦d≦4 and 1≦a+d≦5; when d≧2, each R ^d may be the same or different from each other, and two R d R ^d can also be bonded to each other and form rings together with the atoms to which they are bonded. The peronium compound of claim 2 is represented by the following formula (A-2);

In the formula, Q ¹ ~Q ⁴ , L ^a1 ~ ^{L a4} , XL1 , ^XL2 , R ^a ~R ^d , a, b, c and d are the same as above; ^Re and R ^f are each independently or may contain Monovalent hydrocarbon group with 1-20 carbon atoms of heteroatoms; e is an integer of 0-5; f is an integer of 0-4; when e≧2, each R ^e may be the same or different from each other, and two R ^e may also be They are bonded to each other and form a ring together with the atoms to which they are bonded; when f≧2, each R ^f can be the same or different from each other, and 2 R ^f can also be bonded to each other and form a ring together with the atoms to which they are bonded . The peronium compound of claim 3 is represented by the following formula (A-3);

In the formula, Q ¹ to Q ³ , L ^a1 to ^{L a4} , XL1 , ^XL2 , R ^a to R ^f , a, b, d, e and f are the same as described above. A photoacid generator comprising the perionium compound according to any one of claims 1 to 4. A chemically amplified photoresist composition comprising: a photoacid generator as claimed in claim 5; and a base resin containing a repeating unit represented by the following formula (a1) or (a2);

In the formula, R ^A is each independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; Z ^A is a single bond, a phenylene extension, a naphthylene group or (main chain)-C(=O)-OZ ^A1 -, Z ^A1 is an alkanediyl group with 1 to 10 carbon atoms, or a phenylene extension or a naphthylene group that can also contain a hydroxyl group, an ether bond, an ester bond or a lactone ring; Z ^B is a single bond or (main chain)- C(=O)-O-; X ^A and X ^B are each independently an acid-labile group; R ¹¹ is a monovalent hydrocarbon group with 1-20 carbon atoms which may also contain a hetero atom; n is an integer of 0-4. The chemically amplified photoresist composition of claim 6, wherein the base resin further contains a repeating unit represented by the following formula (b1) or (b2);

In the formula, R ^A is each independently ^a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; Polar group of at least one structure among ester bond, carbonate bond, lactone ring, sultone ring and carboxylic acid anhydride; m is 1 or 2. The chemically amplified photoresist composition of claim 6 or 7, wherein the base resin further contains at least one kind of repeating units selected from the following formulae (c1) to (c3);

In the formula, R ^A is each independently a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group; Z ¹ is a single bond, a phenylene group, -OZ ¹¹ -, -C(=O)-OZ ¹¹ - or - C(=O)-NH-Z ¹¹ -; Z ¹¹ is an alkanediyl group with a carbon number of 1 to 20, an alkenediyl group with a carbon number of 2 to 20 or a phenylene group, and may also contain a carbonyl group, an ester bond, an ether bond or Hydroxyl; Z ² is a single bond, or -Z ²¹ -C(=O)-O-; Z ²¹ is a divalent hydrocarbon group with 1 to 20 carbon atoms that can also contain heteroatoms; Z ³ is a single bond, a methylene group , ethylidene, phenylene, fluorinated phenylene, -OZ ³¹ -, -C(=O)-OZ ³¹ - or -C(=O)-NH-Z ³¹ -; Z ³¹ is carbon number 1 Alkanediyl of ~6, alkenediyl of 2 to 6 carbons, or phenylene, may also contain carbonyl, ester bond, ether bond or hydroxyl; R ²¹ and R ²² are each independently a carbon that may also contain heteroatoms A monovalent hydrocarbon group of 1 to 20; R ²¹ and R ²² can also be bonded to each other and form a ring together with the sulfur atom they are bonded to; M ^- is a non-nucleophilic relative ion; A ⁺ is an ammonium cation, a strontium cation or iodonium cation. The chemically amplified photoresist composition of claim 6 or 7 further contains an organic solvent. The chemically amplified photoresist composition as claimed in claim 6 or 7 further contains other photoacid generators than the photoacid generator as claimed in claim 5. The chemically amplified photoresist composition of claim 10, wherein the other photoacid generator is represented by the following formula (1) or (2);

In the formula, R ¹⁰¹ , R ¹⁰² and R ¹⁰³ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom; and any two of R ¹⁰¹ , R ¹⁰² and R ¹⁰³ may be bonded to each other. Combine and form a ring together with the sulfur atom they are bonded to; X ^- is an anion selected from the following formulas (1A)~(1D); R ^fa -CF ₂ -SO ₃ ^- (1A)

In the formula, R ^fa , R ^fb1 , R ^fb2 , R ^fc1 , R ^fc2 and R ^fc3 are each independently a fluorine atom, or a monovalent hydrocarbon group with 1 to 40 carbon atoms that may also contain heteroatoms; and R ^fb1 and R ^fb2 , and R ^fc1 and R ^fc2 can also be bonded to each other and form a ring together with the carbon atoms to which they are bonded and the atoms in between; R ^fd is a monovalent hydrocarbon group with 1 to 40 carbon atoms that may also contain heteroatoms ;

In the formula, R ²⁰¹ and R ²⁰² are each independently a monovalent hydrocarbon group with a carbon number of 1 to 30 that can also contain a heteroatom; R ²⁰³ is a divalent hydrocarbon group with a carbon number of 1 to 30 that can also contain a heteroatom; and, R Any 2 of ²⁰¹ , R ²⁰² and R ²⁰³ can also be bonded to each other and form a ring together with the sulfur atom they are bonded to; L ^A is a single bond, an ether bond, or a carbon number 1~ A divalent hydrocarbon group of 20; X ^a , X ^b , X ^c and X ^d are each independently a hydrogen atom, a fluorine atom or a trifluoromethyl group, but at least one of X ^a , X ^b , X ^c and X ^d is Fluorine atom or trifluoromethyl group. As claimed in claim 6 or 7, the chemically amplified photoresist composition further contains a compound represented by the following formula (3) or (4);

In the formula, R ^q1 is a hydrogen atom, or a monovalent hydrocarbon group with a carbon number of 1 to 40 that may also contain a heteroatom, but the hydrogen atom bonded to the carbon atom at the α position of the sulfo group is substituted by a fluorine atom or a fluoroalkyl group Except; R ^q2 is a hydrogen atom, or a monovalent hydrocarbon group with a carbon number of 1 to 40 that can also contain a hetero atom; Mq ⁺ is an onium cation. The chemically amplified photoresist composition of claim 6 or 7 further contains an amine compound. As claimed in claim 6 or 7, the chemically amplified photoresist composition further contains a surfactant that is insoluble or poorly soluble in water but soluble in an alkaline developer, and/or is insoluble or poorly soluble in water and an alkaline developer. agent. A pattern forming method, comprising the following steps: forming a photoresist film on a substrate using the chemically amplified photoresist composition according to any one of claims 6 to 14; using KrF excimer laser light, ArF excimer laser light for the photoresist film Expose with laser light, electron beam or extreme ultraviolet ray; and develop the exposed photoresist film with a developing solution. As in the pattern forming method of claim 15, an alkaline aqueous solution is used as a developing solution to dissolve the exposed portion to obtain a positive pattern in which the unexposed portion is insoluble. As in the pattern forming method of claim 15, an organic solvent is used as a developing solution to dissolve the unexposed part to obtain a negative pattern in which the exposed part does not dissolve. The pattern forming method of claim 17, wherein the organic solvent is selected from the group consisting of 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone Ketone, Diisobutylketone, Methylcyclohexanone, Acetophenone, Methylacetophenone, Propyl Acetate, Butyl Acetate, Isobutyl Acetate, Amyl Acetate, Butenyl Acetate, Isoamyl Acetate , propyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl crotonate, ethyl crotonate, methyl propionate, propyl Ethyl Lactate, Ethyl 3-Ethoxypropionate, Methyl Lactate, Ethyl Lactate, Propyl Lactate, Butyl Lactate, Isobutyl Lactate, Amyl Lactate, Isoamyl Lactate, 2-Hydroxyisobutyric Acid methyl ester, ethyl 2-hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, phenyl methyl acetate, benzyl formate, phenylethyl formate, 3-phenyl At least one of methyl propionate, benzyl propionate, ethyl phenylacetate and 2-phenylethyl acetate. The pattern forming method according to any one of claims 15 to 18, wherein the exposure is immersion exposure performed by inserting a liquid having a refractive index of 1.0 or more between the photoresist film and the projection lens. The pattern forming method of claim 19, wherein a protective film is further formed on the photoresist film, the liquid is inserted between the protective film and the projection lens, and immersion exposure is performed.

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